diff --git a/src/api.proposed.kernelStartHook.d.ts b/src/api.proposed.kernelStartHook.d.ts
index 5377ee50f08..3b298851726 100644
--- a/src/api.proposed.kernelStartHook.d.ts
+++ b/src/api.proposed.kernelStartHook.d.ts
@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
-import type { Event, Uri } from 'vscode';
+import type { CancellationToken, Event, Uri } from 'vscode';
 
 declare module './api' {
     export interface Kernels {
@@ -11,6 +11,16 @@ declare module './api' {
         onDidStart: Event<{
             uri: Uri;
             kernel: Kernel;
+            token: CancellationToken;
+            /**
+             * Allows to pause the event loop until the provided thenable resolved.
+             * This can be useful to ensure startup code is executed before user code.
+             *
+             * *Note:* This function can only be called during event dispatch.
+             *
+             * @param thenable A thenable that delays kernel startup.
+             */
+            waitUntil(thenable: Thenable<unknown>): void;
         }>;
     }
 }
diff --git a/src/gdpr.ts b/src/gdpr.ts
index 36c6812749a..aeeb04708e9 100644
--- a/src/gdpr.ts
+++ b/src/gdpr.ts
@@ -592,7 +592,18 @@
      ]
    }
  */
-// (47). Telemetry.NewJupyterKernelApiUsage (DATASCIENCE.JUPYTER_NEW_KERNEL_API_USAGE)
+// (47). Telemetry.NewJupyterKernelApiKernelStartupWaitUntil (DATASCIENCE.JUPYTER_NEW_KERNEL_API_KERNEL_STARTUP_WAIT_UNTIL)
+// Telemetry sent when an extension uses our 3rd party Kernel onDidStart API and calls waitUntil.
+/* __GDPR__
+   "DATASCIENCE.JUPYTER_NEW_KERNEL_API_KERNEL_STARTUP_WAIT_UNTIL" : {
+     "extensionId": {"classification":"PublicNonPersonalData","purpose":"FeatureInsight","comment":"Extension Id that's attempting to use the API.","owner":"donjayamanne"},
+     "${include}": [
+       "${F1}"
+
+     ]
+   }
+ */
+// (48). Telemetry.NewJupyterKernelApiUsage (DATASCIENCE.JUPYTER_NEW_KERNEL_API_USAGE)
 // Telemetry sent when an extension uses our 3rd party Kernel Execution API.
 /* __GDPR__
    "DATASCIENCE.JUPYTER_NEW_KERNEL_API_USAGE" : {
@@ -606,7 +617,7 @@
      ]
    }
  */
-// (48). Telemetry.NewJupyterKernelsApiUsage (DATASCIENCE.JUPYTER_NEW_KERNELS_API_USAGE)
+// (49). Telemetry.NewJupyterKernelsApiUsage (DATASCIENCE.JUPYTER_NEW_KERNELS_API_USAGE)
 // Telemetry sent when an extension uses our 3rd party Kernels API.
 /* __GDPR__
    "DATASCIENCE.JUPYTER_NEW_KERNELS_API_USAGE" : {
@@ -619,7 +630,7 @@
      ]
    }
  */
-// (49). Telemetry.NativeNotebookEditPerformance (DATASCIENCE.JUPYTER_NOTEBOOK_EDIT_PERFORMANCE)
+// (50). Telemetry.NativeNotebookEditPerformance (DATASCIENCE.JUPYTER_NOTEBOOK_EDIT_PERFORMANCE)
 // Telemetry sent during test on CI to measure performance of execution of large notebooks.
 /* __GDPR__
    "DATASCIENCE.JUPYTER_NOTEBOOK_EDIT_PERFORMANCE" : {
@@ -631,7 +642,7 @@
      ]
    }
  */
-// (50). Telemetry.NativeNotebookExecutionPerformance (DATASCIENCE.JUPYTER_NOTEBOOK_EXEC_PERFORMANCE)
+// (51). Telemetry.NativeNotebookExecutionPerformance (DATASCIENCE.JUPYTER_NOTEBOOK_EXEC_PERFORMANCE)
 // Telemetry sent during test on CI to measure performance of execution of large notebooks.
 /* __GDPR__
    "DATASCIENCE.JUPYTER_NOTEBOOK_EXEC_PERFORMANCE" : {
@@ -647,7 +658,7 @@
      ]
    }
  */
-// (51). Telemetry.KernelCrash (DATASCIENCE.KERNEL_CRASH)
+// (52). Telemetry.KernelCrash (DATASCIENCE.KERNEL_CRASH)
 // Sent when Kernel crashes.
 /* __GDPR__
    "DATASCIENCE.KERNEL_CRASH" : {
@@ -674,7 +685,7 @@
      ]
    }
  */
-// (52). Telemetry.KernelSpecLanguage (DATASCIENCE.KERNEL_SPEC_LANGUAGE)
+// (53). Telemetry.KernelSpecLanguage (DATASCIENCE.KERNEL_SPEC_LANGUAGE)
 // Sent to detect the different languages of kernel specs used.
 /* __GDPR__
    "DATASCIENCE.KERNEL_SPEC_LANGUAGE" : {
@@ -687,7 +698,7 @@
      ]
    }
  */
-// (53). Telemetry.OpenNotebookAll (DATASCIENCE.NATIVE.OPEN_NOTEBOOK_ALL)
+// (54). Telemetry.OpenNotebookAll (DATASCIENCE.NATIVE.OPEN_NOTEBOOK_ALL)
 // Sent when we have opened any Jupyter notebook in a VS Code session.
 // Not tagging as a user action as this could be something like auto opening a file
 // from a previous session and not a direct user action.
@@ -701,7 +712,7 @@
      ]
    }
  */
-// (54). Telemetry.NoActiveKernelSession (DATASCIENCE.NO_ACTIVE_KERNEL_SESSION)
+// (55). Telemetry.NoActiveKernelSession (DATASCIENCE.NO_ACTIVE_KERNEL_SESSION)
 // Send when we want to install data viewer dependendies, but don't have an active kernel session.
 // Used by the dataViewerDependencyService.
 /* __GDPR__
@@ -712,7 +723,7 @@
      ]
    }
  */
-// (55). Telemetry.NotebookFirstKernelAutoSelectionBreakDown (DATASCIENCE.NOTEBOOK_FIRST_KERNEL_AUTO_SELECTION_BREAKDOWN)
+// (56). Telemetry.NotebookFirstKernelAutoSelectionBreakDown (DATASCIENCE.NOTEBOOK_FIRST_KERNEL_AUTO_SELECTION_BREAKDOWN)
 // This event is sent to measure the times involved in automatically selecting the first kernel of a notebook.
 /* __GDPR__
    "DATASCIENCE.NOTEBOOK_FIRST_KERNEL_AUTO_SELECTION_BREAKDOWN" : {
@@ -745,7 +756,7 @@
      ]
    }
  */
-// (56). Telemetry.NotebookFirstStartBreakDown (DATASCIENCE.NOTEBOOK_FIRST_START_BREAKDOWN)
+// (57). Telemetry.NotebookFirstStartBreakDown (DATASCIENCE.NOTEBOOK_FIRST_START_BREAKDOWN)
 // This event is sent to measure the times involved in various parts of extension when running a cell.
 // The reference time is `openedAfter` (time when the notebook was opened).
 // All other times are relative to this time, except in the case where a notebook was already opened before the extension was activated.
@@ -804,7 +815,7 @@
      ]
    }
  */
-// (57). Telemetry.NotebookInterrupt (DATASCIENCE.NOTEBOOK_INTERRUPT)
+// (58). Telemetry.NotebookInterrupt (DATASCIENCE.NOTEBOOK_INTERRUPT)
 // Telemetry sent when user interrupts the kernel.
 // Check the `resourceType` to determine whether its a Jupyter Notebook or IW.
 /* __GDPR__
@@ -833,7 +844,7 @@
      ]
    }
  */
-// (58). Telemetry.NotebookRestart (DATASCIENCE.NOTEBOOK_RESTART)
+// (59). Telemetry.NotebookRestart (DATASCIENCE.NOTEBOOK_RESTART)
 // Telemetry sent when user Restarts the Kernel.
 // Check the `resourceType` to determine whether its a Jupyter Notebook or IW.
 /* __GDPR__
@@ -861,7 +872,7 @@
      ]
    }
  */
-// (59). Telemetry.NotebookStart (DATASCIENCE.NOTEBOOK_START)
+// (60). Telemetry.NotebookStart (DATASCIENCE.NOTEBOOK_START)
 // Send when a kernel starts.
 /* __GDPR__
    "DATASCIENCE.NOTEBOOK_START" : {
@@ -888,7 +899,7 @@
      ]
    }
  */
-// (60). Telemetry.OpenPlotViewer (DATASCIENCE.OPEN_PLOT_VIEWER)
+// (61). Telemetry.OpenPlotViewer (DATASCIENCE.OPEN_PLOT_VIEWER)
 // A new instance of the plot viewer was opened.
 /* __GDPR__
    "DATASCIENCE.OPEN_PLOT_VIEWER" : {
@@ -898,7 +909,7 @@
      ]
    }
  */
-// (61). Telemetry.PythonVariableFetchingCodeFailure (DATASCIENCE.PYTHON_VARIABLE_FETCHING_CODE_FAILURE)
+// (62). Telemetry.PythonVariableFetchingCodeFailure (DATASCIENCE.PYTHON_VARIABLE_FETCHING_CODE_FAILURE)
 // The Python code that we ran to fetch variables had a failure.
 /* __GDPR__
    "DATASCIENCE.PYTHON_VARIABLE_FETCHING_CODE_FAILURE" : {
@@ -908,7 +919,7 @@
      ]
    }
  */
-// (62). Telemetry.RecommendExtension (DATASCIENCE.RECOMMENT_EXTENSION)
+// (63). Telemetry.RecommendExtension (DATASCIENCE.RECOMMENT_EXTENSION)
 // Telemetry sent when we recommend installing an extension.
 /* __GDPR__
    "DATASCIENCE.RECOMMENT_EXTENSION" : {
@@ -920,7 +931,7 @@
      ]
    }
  */
-// (63). Telemetry.RefreshDataViewer (DATASCIENCE.REFRESH_DATA_VIEWER)
+// (64). Telemetry.RefreshDataViewer (DATASCIENCE.REFRESH_DATA_VIEWER)
 // Sent when the jupyter.refreshDataViewer command is invoked
 /* __GDPR__
    "DATASCIENCE.REFRESH_DATA_VIEWER" : {
@@ -930,7 +941,7 @@
      ]
    }
  */
-// (64). Telemetry.ResumeCellExecution (DATASCIENCE.RESUME_EXECUTE_CELL)
+// (65). Telemetry.ResumeCellExecution (DATASCIENCE.RESUME_EXECUTE_CELL)
 // Sent when we resume execution of a cell (e.g. when reloading VS Code while a cell was executing).
 /* __GDPR__
    "DATASCIENCE.RESUME_EXECUTE_CELL" : {
@@ -957,7 +968,7 @@
      ]
    }
  */
-// (65). Telemetry.RunAllCells (DATASCIENCE.RUN_ALL_CELLS)
+// (66). Telemetry.RunAllCells (DATASCIENCE.RUN_ALL_CELLS)
 // Command to Run all cells from the active python file in the Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_ALL_CELLS" : {
@@ -967,7 +978,7 @@
      ]
    }
  */
-// (66). Telemetry.RunAllCellsAbove (DATASCIENCE.RUN_ALL_CELLS_ABOVE)
+// (67). Telemetry.RunAllCellsAbove (DATASCIENCE.RUN_ALL_CELLS_ABOVE)
 // Command to Run all the above cells in the Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_ALL_CELLS_ABOVE" : {
@@ -977,7 +988,7 @@
      ]
    }
  */
-// (67). Telemetry.RunByLineVariableHover (DATASCIENCE.RUN_BY_LINE_VARIABLE_HOVER)
+// (68). Telemetry.RunByLineVariableHover (DATASCIENCE.RUN_BY_LINE_VARIABLE_HOVER)
 // Fired when a user hovers a variable while debugging the IW.
 /* __GDPR__
    "DATASCIENCE.RUN_BY_LINE_VARIABLE_HOVER" : {
@@ -987,7 +998,7 @@
      ]
    }
  */
-// (68). Telemetry.RunCellAndAllBelow (DATASCIENCE.RUN_CELL_AND_ALL_BELOW)
+// (69). Telemetry.RunCellAndAllBelow (DATASCIENCE.RUN_CELL_AND_ALL_BELOW)
 // Command to Run current cell and all below in the Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_CELL_AND_ALL_BELOW" : {
@@ -997,7 +1008,7 @@
      ]
    }
  */
-// (69). Telemetry.ChangeCellToCode (DATASCIENCE.RUN_CHANGE_CELL_TO_CODE)
+// (70). Telemetry.ChangeCellToCode (DATASCIENCE.RUN_CHANGE_CELL_TO_CODE)
 // Cell Edit Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_CHANGE_CELL_TO_CODE" : {
@@ -1007,7 +1018,7 @@
      ]
    }
  */
-// (70). Telemetry.ChangeCellToMarkdown (DATASCIENCE.RUN_CHANGE_CELL_TO_MARKDOWN)
+// (71). Telemetry.ChangeCellToMarkdown (DATASCIENCE.RUN_CHANGE_CELL_TO_MARKDOWN)
 // Cell Edit Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_CHANGE_CELL_TO_MARKDOWN" : {
@@ -1017,7 +1028,7 @@
      ]
    }
  */
-// (71). Telemetry.RunCurrentCell (DATASCIENCE.RUN_CURRENT_CELL)
+// (72). Telemetry.RunCurrentCell (DATASCIENCE.RUN_CURRENT_CELL)
 // Command to Run the current Cell in the Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_CURRENT_CELL" : {
@@ -1027,7 +1038,7 @@
      ]
    }
  */
-// (72). Telemetry.RunCurrentCellAndAddBelow (DATASCIENCE.RUN_CURRENT_CELL_AND_ADD_BELOW)
+// (73). Telemetry.RunCurrentCellAndAddBelow (DATASCIENCE.RUN_CURRENT_CELL_AND_ADD_BELOW)
 // Run the cell and everything below it in the Interactive Window.
 /* __GDPR__
    "DATASCIENCE.RUN_CURRENT_CELL_AND_ADD_BELOW" : {
@@ -1037,7 +1048,7 @@
      ]
    }
  */
-// (73). Telemetry.RunCurrentCellAndAdvance (DATASCIENCE.RUN_CURRENT_CELL_AND_ADVANCE)
+// (74). Telemetry.RunCurrentCellAndAdvance (DATASCIENCE.RUN_CURRENT_CELL_AND_ADVANCE)
 // Command to Run current cell in the Interactive Window and advance cursor to the next cell
 /* __GDPR__
    "DATASCIENCE.RUN_CURRENT_CELL_AND_ADVANCE" : {
@@ -1047,7 +1058,7 @@
      ]
    }
  */
-// (74). Telemetry.DeleteCells (DATASCIENCE.RUN_DELETE_CELLS)
+// (75). Telemetry.DeleteCells (DATASCIENCE.RUN_DELETE_CELLS)
 // Cell Edit Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_DELETE_CELLS" : {
@@ -1057,7 +1068,7 @@
      ]
    }
  */
-// (75). Telemetry.ExtendSelectionByCellAbove (DATASCIENCE.RUN_EXTEND_SELECTION_BY_CELL_ABOVE)
+// (76). Telemetry.ExtendSelectionByCellAbove (DATASCIENCE.RUN_EXTEND_SELECTION_BY_CELL_ABOVE)
 // Cell Selection Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_EXTEND_SELECTION_BY_CELL_ABOVE" : {
@@ -1067,7 +1078,7 @@
      ]
    }
  */
-// (76). Telemetry.ExtendSelectionByCellBelow (DATASCIENCE.RUN_EXTEND_SELECTION_BY_CELL_BELOW)
+// (77). Telemetry.ExtendSelectionByCellBelow (DATASCIENCE.RUN_EXTEND_SELECTION_BY_CELL_BELOW)
 // Cell Selection Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_EXTEND_SELECTION_BY_CELL_BELOW" : {
@@ -1077,7 +1088,7 @@
      ]
    }
  */
-// (77). Telemetry.RunFileInteractive (DATASCIENCE.RUN_FILE_INTERACTIVE)
+// (78). Telemetry.RunFileInteractive (DATASCIENCE.RUN_FILE_INTERACTIVE)
 // Command to Run the active file in the Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_FILE_INTERACTIVE" : {
@@ -1087,7 +1098,7 @@
      ]
    }
  */
-// (78). Telemetry.RunFromLine (DATASCIENCE.RUN_FROM_LINE)
+// (79). Telemetry.RunFromLine (DATASCIENCE.RUN_FROM_LINE)
 // Command to Run the active file contents from the cursor location in the Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_FROM_LINE" : {
@@ -1097,7 +1108,7 @@
      ]
    }
  */
-// (79). Telemetry.InsertCellAbove (DATASCIENCE.RUN_INSERT_CELL_ABOVE)
+// (80). Telemetry.InsertCellAbove (DATASCIENCE.RUN_INSERT_CELL_ABOVE)
 // Cell Edit Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_INSERT_CELL_ABOVE" : {
@@ -1107,7 +1118,7 @@
      ]
    }
  */
-// (80). Telemetry.InsertCellBelow (DATASCIENCE.RUN_INSERT_CELL_BELOW)
+// (81). Telemetry.InsertCellBelow (DATASCIENCE.RUN_INSERT_CELL_BELOW)
 // Cell Edit Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_INSERT_CELL_BELOW" : {
@@ -1117,7 +1128,7 @@
      ]
    }
  */
-// (81). Telemetry.InsertCellBelowPosition (DATASCIENCE.RUN_INSERT_CELL_BELOW_POSITION)
+// (82). Telemetry.InsertCellBelowPosition (DATASCIENCE.RUN_INSERT_CELL_BELOW_POSITION)
 // Cell Edit Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_INSERT_CELL_BELOW_POSITION" : {
@@ -1127,7 +1138,7 @@
      ]
    }
  */
-// (82). Telemetry.MoveCellsDown (DATASCIENCE.RUN_MOVE_CELLS_DOWN)
+// (83). Telemetry.MoveCellsDown (DATASCIENCE.RUN_MOVE_CELLS_DOWN)
 // Cell Edit Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_MOVE_CELLS_DOWN" : {
@@ -1137,7 +1148,7 @@
      ]
    }
  */
-// (83). Telemetry.MoveCellsUp (DATASCIENCE.RUN_MOVE_CELLS_UP)
+// (84). Telemetry.MoveCellsUp (DATASCIENCE.RUN_MOVE_CELLS_UP)
 // Cell Edit Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_MOVE_CELLS_UP" : {
@@ -1147,7 +1158,7 @@
      ]
    }
  */
-// (84). Telemetry.SelectCell (DATASCIENCE.RUN_SELECT_CELL)
+// (85). Telemetry.SelectCell (DATASCIENCE.RUN_SELECT_CELL)
 // Cell Selection Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_SELECT_CELL" : {
@@ -1157,7 +1168,7 @@
      ]
    }
  */
-// (85). Telemetry.SelectCellContents (DATASCIENCE.RUN_SELECT_CELL_CONTENTS)
+// (86). Telemetry.SelectCellContents (DATASCIENCE.RUN_SELECT_CELL_CONTENTS)
 // Cell Selection Command in Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_SELECT_CELL_CONTENTS" : {
@@ -1167,7 +1178,7 @@
      ]
    }
  */
-// (86). Telemetry.RunSelectionOrLine (DATASCIENCE.RUN_SELECTION_OR_LINE)
+// (87). Telemetry.RunSelectionOrLine (DATASCIENCE.RUN_SELECTION_OR_LINE)
 // Command to Run a Selection or Line in the Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_SELECTION_OR_LINE" : {
@@ -1177,7 +1188,7 @@
      ]
    }
  */
-// (87). Telemetry.RunToLine (DATASCIENCE.RUN_TO_LINE)
+// (88). Telemetry.RunToLine (DATASCIENCE.RUN_TO_LINE)
 // Command to Run the active file contents up to the cursor location in the Interactive Window
 /* __GDPR__
    "DATASCIENCE.RUN_TO_LINE" : {
@@ -1187,7 +1198,7 @@
      ]
    }
  */
-// (88). Telemetry.SelfCertsMessageClose (DATASCIENCE.SELFCERTSMESSAGECLOSE)
+// (89). Telemetry.SelfCertsMessageClose (DATASCIENCE.SELFCERTSMESSAGECLOSE)
 // Sent when users chose not to allow connecting to Jupyter over HTTPS when certificate isn't trusted by a trusted CA.
 /* __GDPR__
    "DATASCIENCE.SELFCERTSMESSAGECLOSE" : {
@@ -1197,7 +1208,7 @@
      ]
    }
  */
-// (89). Telemetry.SelfCertsMessageEnabled (DATASCIENCE.SELFCERTSMESSAGEENABLED)
+// (90). Telemetry.SelfCertsMessageEnabled (DATASCIENCE.SELFCERTSMESSAGEENABLED)
 // Sent when users chose to use self-signed certificates when connecting to Jupyter over https.
 // Basically this means users has chosen to connect to Jupyter over HTTPS when certificate isn't trusted by a trusted CA.
 /* __GDPR__
@@ -1208,7 +1219,7 @@
      ]
    }
  */
-// (90). Telemetry.ShowDataViewer (DATASCIENCE.SHOW_DATA_EXPLORER)
+// (91). Telemetry.ShowDataViewer (DATASCIENCE.SHOW_DATA_EXPLORER)
 // Request was made to show the data viewer with specific data frame info.
 /* __GDPR__
    "DATASCIENCE.SHOW_DATA_EXPLORER" : {
@@ -1220,7 +1231,7 @@
      ]
    }
  */
-// (91). Telemetry.ShowDataViewerRowsLoaded (DATASCIENCE.SHOW_DATA_EXPLORER_ROWS_LOADED)
+// (92). Telemetry.ShowDataViewerRowsLoaded (DATASCIENCE.SHOW_DATA_EXPLORER_ROWS_LOADED)
 // Data viewer loads rows in chunks, this event is sent when the rows have all been loaded
 /* __GDPR__
    "DATASCIENCE.SHOW_DATA_EXPLORER_ROWS_LOADED" : {
@@ -1231,7 +1242,7 @@
      ]
    }
  */
-// (92). Telemetry.StartShowDataViewer (DATASCIENCE.START_SHOW_DATA_EXPLORER)
+// (93). Telemetry.StartShowDataViewer (DATASCIENCE.START_SHOW_DATA_EXPLORER)
 // User requested to open the data frame viewer.
 /* __GDPR__
    "DATASCIENCE.START_SHOW_DATA_EXPLORER" : {
@@ -1241,7 +1252,7 @@
      ]
    }
  */
-// (93). Telemetry.UserDidNotInstallJupyter (DATASCIENCE.USER_DID_NOT_INSTALL_JUPYTER)
+// (94). Telemetry.UserDidNotInstallJupyter (DATASCIENCE.USER_DID_NOT_INSTALL_JUPYTER)
 // Sent when user click `cancel` button when prompted to install Jupyter.
 /* __GDPR__
    "DATASCIENCE.USER_DID_NOT_INSTALL_JUPYTER" : {
@@ -1251,7 +1262,7 @@
      ]
    }
  */
-// (94). Telemetry.UserDidNotInstallPandas (DATASCIENCE.USER_DID_NOT_INSTALL_PANDAS)
+// (95). Telemetry.UserDidNotInstallPandas (DATASCIENCE.USER_DID_NOT_INSTALL_PANDAS)
 // Prompted to install Pandas and chose not to install
 // Note: This could be just ignoring the UI so not a user action.
 /* __GDPR__
@@ -1262,7 +1273,7 @@
      ]
    }
  */
-// (95). Telemetry.UserInstalledJupyter (DATASCIENCE.USER_INSTALLED_JUPYTER)
+// (96). Telemetry.UserInstalledJupyter (DATASCIENCE.USER_INSTALLED_JUPYTER)
 // Sent when user installs Jupyter.
 /* __GDPR__
    "DATASCIENCE.USER_INSTALLED_JUPYTER" : {
@@ -1272,7 +1283,7 @@
      ]
    }
  */
-// (96). Telemetry.UserInstalledPandas (DATASCIENCE.USER_INSTALLED_PANDAS)
+// (97). Telemetry.UserInstalledPandas (DATASCIENCE.USER_INSTALLED_PANDAS)
 // Installed the python Pandas package.
 /* __GDPR__
    "DATASCIENCE.USER_INSTALLED_PANDAS" : {
@@ -1282,7 +1293,7 @@
      ]
    }
  */
-// (97). Telemetry.DataViewerUsingInterpreter (DATAVIEWER.USING_INTERPRETER)
+// (98). Telemetry.DataViewerUsingInterpreter (DATAVIEWER.USING_INTERPRETER)
 // When the Data Viewer installer is using a Python interpreter to do the install.
 /* __GDPR__
    "DATAVIEWER.USING_INTERPRETER" : {
@@ -1292,7 +1303,7 @@
      ]
    }
  */
-// (98). Telemetry.DataViewerUsingKernel (DATAVIEWER.USING_KERNEL)
+// (99). Telemetry.DataViewerUsingKernel (DATAVIEWER.USING_KERNEL)
 // When the Data Viewer installer is using the Kernel to do the install.
 /* __GDPR__
    "DATAVIEWER.USING_KERNEL" : {
@@ -1302,7 +1313,7 @@
      ]
    }
  */
-// (99). Telemetry.DataViewerWebviewLoaded (DATAVIEWER.WEBVIEW_LOADED)
+// (100). Telemetry.DataViewerWebviewLoaded (DATAVIEWER.WEBVIEW_LOADED)
 // The Data Viewer webview was loaded.
 /* __GDPR__
    "DATAVIEWER.WEBVIEW_LOADED" : {
@@ -1312,7 +1323,7 @@
      ]
    }
  */
-// (100). Telemetry.ActiveInterpreterListingPerf (DS_INTERNAL.ACTIVE_INTERPRETER_LISTING_PERF)
+// (101). Telemetry.ActiveInterpreterListingPerf (DS_INTERNAL.ACTIVE_INTERPRETER_LISTING_PERF)
 // Total time taken by Python extension to return the active Python environment.
 /* __GDPR__
    "DS_INTERNAL.ACTIVE_INTERPRETER_LISTING_PERF" : {
@@ -1323,7 +1334,7 @@
      ]
    }
  */
-// (101). Telemetry.CellOutputMimeType (DS_INTERNAL.CELL_OUTPUT_MIME_TYPE)
+// (102). Telemetry.CellOutputMimeType (DS_INTERNAL.CELL_OUTPUT_MIME_TYPE)
 // Mime type of a cell output.
 // Used to detect the popularity of a mime type, that would help determine which mime types are most common.
 // E.g. if we see widget mimetype, then we know how many use ipywidgets and the like and helps us prioritize widget issues,
@@ -1339,7 +1350,7 @@
      ]
    }
  */
-// (102). Telemetry.CodeLensAverageAcquisitionTime (DS_INTERNAL.CODE_LENS_ACQ_TIME)
+// (103). Telemetry.CodeLensAverageAcquisitionTime (DS_INTERNAL.CODE_LENS_ACQ_TIME)
 // How long on average we spent parsing code lens. Sent on shutdown.
 // We should be able to deprecate in favor of DocumentWithCodeCells, but we should compare the numbers first.
 /* __GDPR__
@@ -1350,7 +1361,7 @@
      ]
    }
  */
-// (103). Telemetry.CommandExecuted (DS_INTERNAL.COMMAND_EXECUTED)
+// (104). Telemetry.CommandExecuted (DS_INTERNAL.COMMAND_EXECUTED)
 // A command that the extension contributes is executed.
 /* __GDPR__
    "DS_INTERNAL.COMMAND_EXECUTED" : {
@@ -1361,7 +1372,7 @@
      ]
    }
  */
-// (104). Telemetry.CreateInteractiveWindow (DS_INTERNAL.CREATED_INTERACTIVE_WINDOW)
+// (105). Telemetry.CreateInteractiveWindow (DS_INTERNAL.CREATED_INTERACTIVE_WINDOW)
 /* __GDPR__
    "DS_INTERNAL.CREATED_INTERACTIVE_WINDOW" : {
      "hasKernel": {"classification":"SystemMetaData","purpose":"FeatureInsight","comment":"If the kernel was known at the time of creation","owner":"amunger"},
@@ -1375,7 +1386,7 @@
      ]
    }
  */
-// (105). Telemetry.DocumentWithCodeCells (DS_INTERNAL.DOCUMENT_WITH_CODE_CELLS)
+// (106). Telemetry.DocumentWithCodeCells (DS_INTERNAL.DOCUMENT_WITH_CODE_CELLS)
 // Info about code lenses, count and average time to parse the document.
 /* __GDPR__
    "DS_INTERNAL.DOCUMENT_WITH_CODE_CELLS" : {
@@ -1387,7 +1398,7 @@
      ]
    }
  */
-// (106). Telemetry.ExperimentLoad (DS_INTERNAL.EXPERIMENT_LOAD)
+// (107). Telemetry.ExperimentLoad (DS_INTERNAL.EXPERIMENT_LOAD)
 // Telemetry event sent with perf measures related to loading experiments.
 /* __GDPR__
    "DS_INTERNAL.EXPERIMENT_LOAD" : {
@@ -1397,7 +1408,7 @@
      ]
    }
  */
-// (107). Telemetry.GetActivatedEnvironmentVariables (DS_INTERNAL.GET_ACTIVATED_ENV_VARIABLES)
+// (108). Telemetry.GetActivatedEnvironmentVariables (DS_INTERNAL.GET_ACTIVATED_ENV_VARIABLES)
 // Used to capture time taken to get environment variables for a python environment.
 // Also lets us know whether it worked or not.
 /* __GDPR__
@@ -1411,7 +1422,7 @@
      ]
    }
  */
-// (108). Telemetry.GetPasswordFailure (DS_INTERNAL.GET_PASSWORD_FAILURE)
+// (109). Telemetry.GetPasswordFailure (DS_INTERNAL.GET_PASSWORD_FAILURE)
 // Sent to indicate we've failed to connect to a Remote Jupyter Server successfully after requesting a password.
 /* __GDPR__
    "DS_INTERNAL.GET_PASSWORD_FAILURE" : {
@@ -1421,7 +1432,7 @@
      ]
    }
  */
-// (109). Telemetry.GetPasswordSuccess (DS_INTERNAL.GET_PASSWORD_SUCCESS)
+// (110). Telemetry.GetPasswordSuccess (DS_INTERNAL.GET_PASSWORD_SUCCESS)
 // Sent to indicate we've connected to a Remote Jupyter Server successfully after requesting a password.
 /* __GDPR__
    "DS_INTERNAL.GET_PASSWORD_SUCCESS" : {
@@ -1431,7 +1442,7 @@
      ]
    }
  */
-// (110). Telemetry.InteractiveFileTooltipsPerf (DS_INTERNAL.INTERACTIVE_FILE_TOOLTIPS_PERF)
+// (111). Telemetry.InteractiveFileTooltipsPerf (DS_INTERNAL.INTERACTIVE_FILE_TOOLTIPS_PERF)
 // How long it took to return our hover tooltips for a .py file.
 /* __GDPR__
    "DS_INTERNAL.INTERACTIVE_FILE_TOOLTIPS_PERF" : {
@@ -1442,7 +1453,7 @@
      ]
    }
  */
-// (111). Telemetry.DiscoverIPyWidgetNamesPerf (DS_INTERNAL.IPYWIDGET_DISCOVER_WIDGETS_NB_EXTENSIONS)
+// (112). Telemetry.DiscoverIPyWidgetNamesPerf (DS_INTERNAL.IPYWIDGET_DISCOVER_WIDGETS_NB_EXTENSIONS)
 // Total time taken to discover all IPyWidgets.
 // This is how long it takes to discover all widgets on disc (from python environment).
 /* __GDPR__
@@ -1454,7 +1465,7 @@
      ]
    }
  */
-// (112). Telemetry.HashedIPyWidgetScriptDiscoveryError (DS_INTERNAL.IPYWIDGET_DISCOVERY_ERRORED)
+// (113). Telemetry.HashedIPyWidgetScriptDiscoveryError (DS_INTERNAL.IPYWIDGET_DISCOVERY_ERRORED)
 // Something went wrong in looking for a widget.
 /* __GDPR__
    "DS_INTERNAL.IPYWIDGET_DISCOVERY_ERRORED" : {
@@ -1464,7 +1475,7 @@
      ]
    }
  */
-// (113). Telemetry.IPyWidgetExtensionJsInfo (DS_INTERNAL.IPYWIDGET_EXTENSIONJS_INFO)
+// (114). Telemetry.IPyWidgetExtensionJsInfo (DS_INTERNAL.IPYWIDGET_EXTENSIONJS_INFO)
 // Telemetry event sent once we've successfully or unsuccessfully parsed the extension.js file in the widget folder.
 // E.g. if we have a widget named ipyvolume, we attempt to parse the nbextensions/ipyvolume/extension.js file to get some info out of it.
 /* __GDPR__
@@ -1479,7 +1490,7 @@
      ]
    }
  */
-// (114). Telemetry.IPyWidgetLoadFailure (DS_INTERNAL.IPYWIDGET_LOAD_FAILURE)
+// (115). Telemetry.IPyWidgetLoadFailure (DS_INTERNAL.IPYWIDGET_LOAD_FAILURE)
 // Telemetry event sent when an ipywidget module fails to load. Module name is hashed.
 /* __GDPR__
    "DS_INTERNAL.IPYWIDGET_LOAD_FAILURE" : {
@@ -1493,7 +1504,7 @@
      ]
    }
  */
-// (115). Telemetry.IPyWidgetLoadSuccess (DS_INTERNAL.IPYWIDGET_LOAD_SUCCESS)
+// (116). Telemetry.IPyWidgetLoadSuccess (DS_INTERNAL.IPYWIDGET_LOAD_SUCCESS)
 // Telemetry event sent when an ipywidget module loads. Module name is hashed.
 /* __GDPR__
    "DS_INTERNAL.IPYWIDGET_LOAD_SUCCESS" : {
@@ -1505,7 +1516,7 @@
      ]
    }
  */
-// (116). Telemetry.IPyWidgetPromptToUseCDN (DS_INTERNAL.IPYWIDGET_PROMPT_TO_USE_CDN)
+// (117). Telemetry.IPyWidgetPromptToUseCDN (DS_INTERNAL.IPYWIDGET_PROMPT_TO_USE_CDN)
 // Telemetry sent when we prompt user to use a CDN for IPyWidget scripts.
 // This is always sent when we display a prompt.
 /* __GDPR__
@@ -1516,7 +1527,7 @@
      ]
    }
  */
-// (117). Telemetry.IPyWidgetPromptToUseCDNSelection (DS_INTERNAL.IPYWIDGET_PROMPT_TO_USE_CDN_SELECTION)
+// (118). Telemetry.IPyWidgetPromptToUseCDNSelection (DS_INTERNAL.IPYWIDGET_PROMPT_TO_USE_CDN_SELECTION)
 // Telemetry sent when user does something with the prompt displayed to user about using CDN for IPyWidget scripts.
 /* __GDPR__
    "DS_INTERNAL.IPYWIDGET_PROMPT_TO_USE_CDN_SELECTION" : {
@@ -1527,7 +1538,7 @@
      ]
    }
  */
-// (118). Telemetry.IPyWidgetRenderFailure (DS_INTERNAL.IPYWIDGET_RENDER_FAILURE)
+// (119). Telemetry.IPyWidgetRenderFailure (DS_INTERNAL.IPYWIDGET_RENDER_FAILURE)
 // Telemetry event sent when the widget render function fails (note, this may not be sufficient to capture all failures).
 /* __GDPR__
    "DS_INTERNAL.IPYWIDGET_RENDER_FAILURE" : {
@@ -1537,7 +1548,7 @@
      ]
    }
  */
-// (119). Telemetry.IPyWidgetNbExtensionCopyTime (DS_INTERNAL.IPYWIDGET_TIME_TO_COPY_NBEXTENSIONS_DIR)
+// (120). Telemetry.IPyWidgetNbExtensionCopyTime (DS_INTERNAL.IPYWIDGET_TIME_TO_COPY_NBEXTENSIONS_DIR)
 // Total time take to copy the nb extensions folder.
 /* __GDPR__
    "DS_INTERNAL.IPYWIDGET_TIME_TO_COPY_NBEXTENSIONS_DIR" : {
@@ -1547,7 +1558,7 @@
      ]
    }
  */
-// (120). Telemetry.IPyWidgetUnhandledMessage (DS_INTERNAL.IPYWIDGET_UNHANDLED_MESSAGE)
+// (121). Telemetry.IPyWidgetUnhandledMessage (DS_INTERNAL.IPYWIDGET_UNHANDLED_MESSAGE)
 // Telemetry event sent when the widget tries to send a kernel message but nothing was listening
 /* __GDPR__
    "DS_INTERNAL.IPYWIDGET_UNHANDLED_MESSAGE" : {
@@ -1558,7 +1569,7 @@
      ]
    }
  */
-// (121). Telemetry.HashedIPyWidgetNameUsed (DS_INTERNAL.IPYWIDGET_USED_BY_USER)
+// (122). Telemetry.HashedIPyWidgetNameUsed (DS_INTERNAL.IPYWIDGET_USED_BY_USER)
 // Telemetry event sent with name of a Widget that is used.
 // Helps determine which widgets are used the most, and which are not.
 // Useful in prioritizing which widgets to work on if things fail to work.
@@ -1576,7 +1587,7 @@
      ]
    }
  */
-// (122). Telemetry.IPyWidgetWidgetVersionNotSupportedLoadFailure (DS_INTERNAL.IPYWIDGET_WIDGET_VERSION_NOT_SUPPORTED_LOAD_FAILURE)
+// (123). Telemetry.IPyWidgetWidgetVersionNotSupportedLoadFailure (DS_INTERNAL.IPYWIDGET_WIDGET_VERSION_NOT_SUPPORTED_LOAD_FAILURE)
 // Telemetry event sent when an ipywidget version that is not supported is used & we have trapped this and warned the user abou it.
 /* __GDPR__
    "DS_INTERNAL.IPYWIDGET_WIDGET_VERSION_NOT_SUPPORTED_LOAD_FAILURE" : {
@@ -1588,7 +1599,7 @@
      ]
    }
  */
-// (123). Telemetry.CheckPasswordJupyterHub (DS_INTERNAL.JUPYTER_HUB_PASSWORD)
+// (124). Telemetry.CheckPasswordJupyterHub (DS_INTERNAL.JUPYTER_HUB_PASSWORD)
 // Sent when checking for passwords for Jupyter Hub
 /* __GDPR__
    "DS_INTERNAL.JUPYTER_HUB_PASSWORD" : {
@@ -1599,7 +1610,7 @@
      ]
    }
  */
-// (124). Telemetry.KernelSpec (DS_INTERNAL.JUPYTER_KERNEL_SPEC)
+// (125). Telemetry.KernelSpec (DS_INTERNAL.JUPYTER_KERNEL_SPEC)
 // Information about KernelSpecs
 /* __GDPR__
    "DS_INTERNAL.JUPYTER_KERNEL_SPEC" : {
@@ -1620,7 +1631,7 @@
      ]
    }
  */
-// (125). Telemetry.ZMQSupport (DS_INTERNAL.JUPYTER_ZMQ_SUPPORT)
+// (126). Telemetry.ZMQSupport (DS_INTERNAL.JUPYTER_ZMQ_SUPPORT)
 // Information used to determine the zmq binary support.
 // the alpine, libc, armv version is used by the node module
 /* __GDPR__
@@ -1638,7 +1649,7 @@
      ]
    }
  */
-// (126). Telemetry.ZMQSupportFailure (DS_INTERNAL.JUPYTER_ZMQ_SUPPORT_FAILURE)
+// (127). Telemetry.ZMQSupportFailure (DS_INTERNAL.JUPYTER_ZMQ_SUPPORT_FAILURE)
 // Information used to determine the zmq binary support.
 // the alpine, libc, armv version is used by the node module
 /* __GDPR__
@@ -1659,7 +1670,7 @@
      ]
    }
  */
-// (127). Telemetry.KernelCount (DS_INTERNAL.KERNEL_COUNT)
+// (128). Telemetry.KernelCount (DS_INTERNAL.KERNEL_COUNT)
 // Telemetry sent with the total number of different types of kernels in the kernel picker.
 /* __GDPR__
    "DS_INTERNAL.KERNEL_COUNT" : {
@@ -1674,7 +1685,7 @@
      ]
    }
  */
-// (128). Telemetry.KernelLauncherPerf (DS_INTERNAL.KERNEL_LAUNCHER_PERF)
+// (129). Telemetry.KernelLauncherPerf (DS_INTERNAL.KERNEL_LAUNCHER_PERF)
 // Total time taken to Launch a raw kernel.
 /* __GDPR__
    "DS_INTERNAL.KERNEL_LAUNCHER_PERF" : {
@@ -1685,7 +1696,7 @@
      ]
    }
  */
-// (129). Telemetry.NativeVariableViewLoaded (DS_INTERNAL.NATIVE_VARIABLE_VIEW_LOADED)
+// (130). Telemetry.NativeVariableViewLoaded (DS_INTERNAL.NATIVE_VARIABLE_VIEW_LOADED)
 // The Variable View webview was loaded.
 /* __GDPR__
    "DS_INTERNAL.NATIVE_VARIABLE_VIEW_LOADED" : {
@@ -1695,7 +1706,7 @@
      ]
    }
  */
-// (130). Telemetry.NativeVariableViewMadeVisible (DS_INTERNAL.NATIVE_VARIABLE_VIEW_MADE_VISIBLE)
+// (131). Telemetry.NativeVariableViewMadeVisible (DS_INTERNAL.NATIVE_VARIABLE_VIEW_MADE_VISIBLE)
 // The Variable View webview was made visible.
 /* __GDPR__
    "DS_INTERNAL.NATIVE_VARIABLE_VIEW_MADE_VISIBLE" : {
@@ -1705,7 +1716,7 @@
      ]
    }
  */
-// (131). Telemetry.NewFileForInteractiveWindow (DS_INTERNAL.NEW_FILE_USED_IN_INTERACTIVE)
+// (132). Telemetry.NewFileForInteractiveWindow (DS_INTERNAL.NEW_FILE_USED_IN_INTERACTIVE)
 // Telemetry event sent when a user runs the interactive window with a new file
 /* __GDPR__
    "DS_INTERNAL.NEW_FILE_USED_IN_INTERACTIVE" : {
@@ -1715,7 +1726,7 @@
      ]
    }
  */
-// (132). Telemetry.PerceivedJupyterStartupNotebook (DS_INTERNAL.PERCEIVED_JUPYTER_STARTUP_NOTEBOOK)
+// (133). Telemetry.PerceivedJupyterStartupNotebook (DS_INTERNAL.PERCEIVED_JUPYTER_STARTUP_NOTEBOOK)
 // Time take for jupyter server to start and be ready to run first user cell.
 // (Note: The property `notebook` only gets sent correctly in Jupyter version 2022.8.0 or later)
 /* __GDPR__
@@ -1743,7 +1754,7 @@
      ]
    }
  */
-// (133). Telemetry.PreferredKernelExactMatch (DS_INTERNAL.PREFERRED_KERNEL_EXACT_MATCH)
+// (134). Telemetry.PreferredKernelExactMatch (DS_INTERNAL.PREFERRED_KERNEL_EXACT_MATCH)
 // Send we we complete our preferred kernel match. Matched reason might be 'no match'.
 /* __GDPR__
    "DS_INTERNAL.PREFERRED_KERNEL_EXACT_MATCH" : {
@@ -1754,7 +1765,7 @@
      ]
    }
  */
-// (134). Telemetry.PythonExtensionInstalledViaKernelPicker (DS_INTERNAL.PYTHON_EXTENSION_INSTALLED_VIA_KERNEL_PICKER)
+// (135). Telemetry.PythonExtensionInstalledViaKernelPicker (DS_INTERNAL.PYTHON_EXTENSION_INSTALLED_VIA_KERNEL_PICKER)
 // Python extension was attempted to be installed via the kernel picker command.
 /* __GDPR__
    "DS_INTERNAL.PYTHON_EXTENSION_INSTALLED_VIA_KERNEL_PICKER" : {
@@ -1765,7 +1776,7 @@
      ]
    }
  */
-// (135). Telemetry.PythonExtensionNotInstalled (DS_INTERNAL.PYTHON_EXTENSION_NOT_INSTALLED)
+// (136). Telemetry.PythonExtensionNotInstalled (DS_INTERNAL.PYTHON_EXTENSION_NOT_INSTALLED)
 // The kernel picker command to install python extension was shown.
 /* __GDPR__
    "DS_INTERNAL.PYTHON_EXTENSION_NOT_INSTALLED" : {
@@ -1776,7 +1787,7 @@
      ]
    }
  */
-// (136). Telemetry.PythonModuleInstall (DS_INTERNAL.PYTHON_MODULE_INSTALL)
+// (137). Telemetry.PythonModuleInstall (DS_INTERNAL.PYTHON_MODULE_INSTALL)
 // Telemetry sent when user is presented with a dialog to install a python package.
 // Also sent with the user's response to the dialog.
 /* __GDPR__
@@ -1793,7 +1804,7 @@
      ]
    }
  */
-// (137). Telemetry.PythonNotInstalled (DS_INTERNAL.PYTHON_NOT_INSTALLED)
+// (138). Telemetry.PythonNotInstalled (DS_INTERNAL.PYTHON_NOT_INSTALLED)
 // The kernel picker command to install python was shown.
 /* __GDPR__
    "DS_INTERNAL.PYTHON_NOT_INSTALLED" : {
@@ -1804,7 +1815,7 @@
      ]
    }
  */
-// (138). Telemetry.RawKernelInfoResponse (DS_INTERNAL.RAWKERNEL_INFO_RESPONSE)
+// (139). Telemetry.RawKernelInfoResponse (DS_INTERNAL.RAWKERNEL_INFO_RESPONSE)
 // After starting a kernel we send a request to get the kernel info.
 // This tracks the total time taken to get the response back (or wether we timedout).
 // If we timeout and later we find successful comms for this session, then timeout is too low
@@ -1836,7 +1847,7 @@
      ]
    }
  */
-// (139). Telemetry.RawKernelProcessLaunch (DS_INTERNAL.RAWKERNEL_PROCESS_LAUNCH)
+// (140). Telemetry.RawKernelProcessLaunch (DS_INTERNAL.RAWKERNEL_PROCESS_LAUNCH)
 // Sent to measure time taken to spawn the raw kernel process.
 /* __GDPR__
    "DS_INTERNAL.RAWKERNEL_PROCESS_LAUNCH" : {
@@ -1846,7 +1857,7 @@
      ]
    }
  */
-// (140). Telemetry.RawKernelSessionDisposed (DS_INTERNAL.RAWKERNEL_SESSION_DISPOSED)
+// (141). Telemetry.RawKernelSessionDisposed (DS_INTERNAL.RAWKERNEL_SESSION_DISPOSED)
 // This event is sent when a RawSession's `dispose` method is called.
 // Used to determine what part of the code that shut down the session, so as to determine when and how the kernel session crashed.
 /* __GDPR__
@@ -1875,7 +1886,7 @@
      ]
    }
  */
-// (141). Telemetry.RawKernelSessionKernelProcessExited (DS_INTERNAL.RAWKERNEL_SESSION_KERNEL_PROCESS_EXITED)
+// (142). Telemetry.RawKernelSessionKernelProcessExited (DS_INTERNAL.RAWKERNEL_SESSION_KERNEL_PROCESS_EXITED)
 // This event is sent when the underlying kernelProcess for a
 // RawJupyterSession exits.
 /* __GDPR__
@@ -1905,7 +1916,7 @@
      ]
    }
  */
-// (142). Telemetry.RawKernelSessionStartNoIpykernel (DS_INTERNAL.RAWKERNEL_SESSION_NO_IPYKERNEL)
+// (143). Telemetry.RawKernelSessionStartNoIpykernel (DS_INTERNAL.RAWKERNEL_SESSION_NO_IPYKERNEL)
 // Telemetry event sent when raw kernel startup fails due to missing ipykernel dependency.
 // This is useful to see what the user does with this error message.
 /* __GDPR__
@@ -1934,7 +1945,7 @@
      ]
    }
  */
-// (143). Telemetry.RawKernelSessionShutdown (DS_INTERNAL.RAWKERNEL_SESSION_SHUTDOWN)
+// (144). Telemetry.RawKernelSessionShutdown (DS_INTERNAL.RAWKERNEL_SESSION_SHUTDOWN)
 // This event is sent when a RawJupyterSession's `shutdownSession` method is called.
 // Used to determine what part of the code that shut down the session, so as to determine when and how the kernel session crashed.
 /* __GDPR__
@@ -1964,7 +1975,7 @@
      ]
    }
  */
-// (144). Telemetry.RunTest (DS_INTERNAL.RUNTEST)
+// (145). Telemetry.RunTest (DS_INTERNAL.RUNTEST)
 // A automated test has been run
 /* __GDPR__
    "DS_INTERNAL.RUNTEST" : {
@@ -1979,7 +1990,7 @@
      ]
    }
  */
-// (145). Telemetry.ShiftEnterBannerShown (DS_INTERNAL.SHIFTENTER_BANNER_SHOWN)
+// (146). Telemetry.ShiftEnterBannerShown (DS_INTERNAL.SHIFTENTER_BANNER_SHOWN)
 // Information banner displayed to give the user the option to configure shift+enter for the Interactive Window.
 /* __GDPR__
    "DS_INTERNAL.SHIFTENTER_BANNER_SHOWN" : {
@@ -1989,7 +2000,7 @@
      ]
    }
  */
-// (146). Telemetry.PandasNotInstalled (DS_INTERNAL.SHOW_DATA_NO_PANDAS)
+// (147). Telemetry.PandasNotInstalled (DS_INTERNAL.SHOW_DATA_NO_PANDAS)
 // User tried to open the data viewer and Pandas package was not installed.
 // Note: Not a failure state, as we prompt for install after this.
 /* __GDPR__
@@ -2000,7 +2011,7 @@
      ]
    }
  */
-// (147). Telemetry.PandasInstallCanceled (DS_INTERNAL.SHOW_DATA_PANDAS_INSTALL_CANCELED)
+// (148). Telemetry.PandasInstallCanceled (DS_INTERNAL.SHOW_DATA_PANDAS_INSTALL_CANCELED)
 // When opening the data viewer the user was prompted to install / upgrade
 // pandas and choose to cancel the operation.
 /* __GDPR__
@@ -2011,7 +2022,7 @@
      ]
    }
  */
-// (148). Telemetry.PandasOK (DS_INTERNAL.SHOW_DATA_PANDAS_OK)
+// (149). Telemetry.PandasOK (DS_INTERNAL.SHOW_DATA_PANDAS_OK)
 // When opening the data viewer the version of Pandas installed was ok.
 /* __GDPR__
    "DS_INTERNAL.SHOW_DATA_PANDAS_OK" : {
@@ -2021,7 +2032,7 @@
      ]
    }
  */
-// (149). Telemetry.PandasTooOld (DS_INTERNAL.SHOW_DATA_PANDAS_TOO_OLD)
+// (150). Telemetry.PandasTooOld (DS_INTERNAL.SHOW_DATA_PANDAS_TOO_OLD)
 // When opening the data viewer the version of Pandas installed was too old.
 /* __GDPR__
    "DS_INTERNAL.SHOW_DATA_PANDAS_TOO_OLD" : {
@@ -2031,7 +2042,7 @@
      ]
    }
  */
-// (150). Telemetry.SwitchKernel (DS_INTERNAL.SWITCH_KERNEL)
+// (151). Telemetry.SwitchKernel (DS_INTERNAL.SWITCH_KERNEL)
 // Triggered when the kernel selection changes (note: This can also happen automatically when a notebook is opened).
 // WARNING: Due to changes in VS Code, this isn't necessarily a user action, hence difficult to tell if the user changed it or it changed automatically.
 /* __GDPR__
@@ -2059,7 +2070,7 @@
      ]
    }
  */
-// (151). Telemetry.VariableExplorerFetchTime (DS_INTERNAL.VARIABLE_EXPLORER_FETCH_TIME)
+// (152). Telemetry.VariableExplorerFetchTime (DS_INTERNAL.VARIABLE_EXPLORER_FETCH_TIME)
 // How long did it take for a single variable request to be resolved.
 /* __GDPR__
    "DS_INTERNAL.VARIABLE_EXPLORER_FETCH_TIME" : {
@@ -2069,7 +2080,7 @@
      ]
    }
  */
-// (152). Telemetry.VariableExplorerVariableCount (DS_INTERNAL.VARIABLE_EXPLORER_VARIABLE_COUNT)
+// (153). Telemetry.VariableExplorerVariableCount (DS_INTERNAL.VARIABLE_EXPLORER_VARIABLE_COUNT)
 // Count how many variables were in a variable request.
 /* __GDPR__
    "DS_INTERNAL.VARIABLE_EXPLORER_VARIABLE_COUNT" : {
@@ -2080,7 +2091,7 @@
      ]
    }
  */
-// (153). Telemetry.VSCNotebookCellTranslationFailed (DS_INTERNAL.VSCNOTEBOOK_CELL_TRANSLATION_FAILED)
+// (154). Telemetry.VSCNotebookCellTranslationFailed (DS_INTERNAL.VSCNOTEBOOK_CELL_TRANSLATION_FAILED)
 // We've failed to translate a Jupyter cell output for serialization into a Notebook cell.
 /* __GDPR__
    "DS_INTERNAL.VSCNOTEBOOK_CELL_TRANSLATION_FAILED" : {
@@ -2091,7 +2102,7 @@
      ]
    }
  */
-// (154). EventName.ENVFILE_VARIABLE_SUBSTITUTION (ENVFILE_VARIABLE_SUBSTITUTION)
+// (155). EventName.ENVFILE_VARIABLE_SUBSTITUTION (ENVFILE_VARIABLE_SUBSTITUTION)
 // Telemetry event sent when substituting Environment variables to calculate value of variables.
 // E.g. user has a a .env file with tokens that need to be replaced with env variables.
 // such as an env file having the variable `${HOME}`.
@@ -2104,7 +2115,7 @@
      ]
    }
  */
-// (155). EventName.ENVFILE_WORKSPACE (ENVFILE_WORKSPACE)
+// (156). EventName.ENVFILE_WORKSPACE (ENVFILE_WORKSPACE)
 // Telemetry event sent when an environment file is detected in the workspace.
 /* __GDPR__
    "ENVFILE_WORKSPACE" : {
@@ -2114,7 +2125,7 @@
      ]
    }
  */
-// (156). EventName.EXTENSION_LOAD (EXTENSION.LOAD)
+// (157). EventName.EXTENSION_LOAD (EXTENSION.LOAD)
 // Telemetry event sent with perf measures related to activation and loading of extension.
 /* __GDPR__
    "EXTENSION.LOAD" : {
@@ -2127,7 +2138,7 @@
      ]
    }
  */
-// (157). Telemetry.AmbiguousGlobalKernelSpec (GLOBAL_PYTHON_KERNELSPEC)
+// (158). Telemetry.AmbiguousGlobalKernelSpec (GLOBAL_PYTHON_KERNELSPEC)
 // We have a Python Kernel spec without fully qualified path of Python env.
 // We have no idea how to start these kernels if the user has more than one Python env.
 //
@@ -2151,7 +2162,7 @@
      ]
    }
  */
-// (158). EventName.HASHED_PACKAGE_NAME (HASHED_PACKAGE_NAME)
+// (159). EventName.HASHED_PACKAGE_NAME (HASHED_PACKAGE_NAME)
 // Telemetry event sent with hash of an imported python package.
 // Used to detect the popularity of a package, that would help determine which packages
 // need to be prioritized when resolving issues with intellisense or supporting similar issues related to a (known) specific package.
@@ -2166,7 +2177,7 @@
      ]
    }
  */
-// (159). EventName.OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_ERROR (OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_ERROR_EX)
+// (160). EventName.OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_ERROR (OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_ERROR_EX)
 // Telemetry event sent when user opens the data viewer via the variable view and there is an error in doing so.
 /* __GDPR__
    "OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_ERROR_EX" : {
@@ -2176,7 +2187,7 @@
      ]
    }
  */
-// (160). EventName.OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_REQUEST (OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_REQUEST_EX)
+// (161). EventName.OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_REQUEST (OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_REQUEST_EX)
 // Telemetry event sent when user opens the data viewer via the variable view.
 /* __GDPR__
    "OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_REQUEST_EX" : {
@@ -2186,7 +2197,7 @@
      ]
    }
  */
-// (161). EventName.OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_SUCCESS (OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_SUCCESS_EX)
+// (162). EventName.OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_SUCCESS (OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_SUCCESS_EX)
 // Telemetry event sent when user opens the data viewer via the variable view and we successfully open the view.
 /* __GDPR__
    "OPEN_DATAVIEWER_FROM_VARIABLE_WINDOW_SUCCESS_EX" : {
@@ -2196,7 +2207,7 @@
      ]
    }
  */
-// (162). Telemetry.PlotViewerWebviewLoaded (PLOTVIEWER.WEBVIEW_LOADED)
+// (163). Telemetry.PlotViewerWebviewLoaded (PLOTVIEWER.WEBVIEW_LOADED)
 // The Plot Viewer webview was loaded.
 /* __GDPR__
    "PLOTVIEWER.WEBVIEW_LOADED" : {
diff --git a/src/kernels/kernel.ts b/src/kernels/kernel.ts
index a63893ad1fb..7afc6f00ddd 100644
--- a/src/kernels/kernel.ts
+++ b/src/kernels/kernel.ts
@@ -15,7 +15,8 @@ import {
     Memento,
     CancellationError,
     window,
-    workspace
+    workspace,
+    CancellationToken
 } from 'vscode';
 import {
     CodeSnippets,
@@ -66,6 +67,7 @@ import { KernelInterruptTimeoutError } from './errors/kernelInterruptTimeoutErro
 import { dispose } from '../platform/common/utils/lifecycle';
 import { getCachedVersion, getEnvironmentType } from '../platform/interpreter/helpers';
 import { getNotebookTelemetryTracker } from './telemetry/notebookTelemetry';
+import { AsyncEmitter } from '../platform/common/utils/events';
 
 const widgetVersionOutPrefix = 'e976ee50-99ed-4aba-9b6b-9dcd5634d07d:IPyWidgets:';
 /**
@@ -129,7 +131,7 @@ abstract class BaseKernel implements IBaseKernel {
     get onStarted(): Event<void> {
         return this._onStarted.event;
     }
-    get onPostInitialized(): Event<void> {
+    get onPostInitialized(): Event<{ token: CancellationToken; waitUntil(thenable: Thenable<unknown>): void }> {
         return this._onPostInitialized.event;
     }
     get onDisposed(): Event<void> {
@@ -178,12 +180,15 @@ abstract class BaseKernel implements IBaseKernel {
     private _disposed?: boolean;
     private _disposing?: boolean;
     private _ignoreJupyterSessionDisposedErrors?: boolean;
-    private _postInitializedOnStart?: boolean;
+    private _postInitializedOnStartPromise?: Promise<void>;
     private readonly _onDidKernelSocketChange = new EventEmitter<void>();
     private readonly _onStatusChanged = new EventEmitter<KernelMessage.Status>();
     private readonly _onRestarted = new EventEmitter<void>();
     private readonly _onStarted = new EventEmitter<void>();
-    private readonly _onPostInitialized = new EventEmitter<void>();
+    private readonly _onPostInitialized = new AsyncEmitter<{
+        waitUntil: (thenable: Thenable<unknown>) => void;
+        token: CancellationToken;
+    }>();
     private readonly _onDisposed = new EventEmitter<void>();
     private _jupyterSessionPromise?: Promise<IKernelSession>;
     private readonly hookedSessionForEvents = new WeakSet<IKernelSession>();
@@ -254,16 +259,9 @@ abstract class BaseKernel implements IBaseKernel {
             this.startCancellation.dispose();
             this.startCancellation = new CancellationTokenSource();
         }
-        return this.startJupyterSession(options).then((result) => {
-            // If we started and the UI is no longer disabled (ie., a user executed a cell)
-            // then we can signal that the kernel was created and can be used by third-party extensions.
-            // We also only want to fire off a single event here.
-            if (!options?.disableUI && !this._postInitializedOnStart) {
-                this._onPostInitialized.fire();
-                this._postInitializedOnStart = true;
-            }
-            return result;
-        });
+        const result = await this.startJupyterSession(options);
+        await this.triggerOnDidStartKernel(options?.disableUI === true, false);
+        return result;
     }
     /**
      * Interrupts the execution of cells.
@@ -335,6 +333,7 @@ abstract class BaseKernel implements IBaseKernel {
                 ? await this._jupyterSessionPromise.catch(() => undefined)
                 : undefined;
             this._jupyterSessionPromise = undefined;
+            this._postInitializedOnStartPromise = undefined;
             if (this._session) {
                 promises.push(disposeAsync(this._session, this.disposables));
                 this._session = undefined;
@@ -404,6 +403,7 @@ abstract class BaseKernel implements IBaseKernel {
                 const session = this._session;
                 this._session = undefined;
                 this._jupyterSessionPromise = undefined;
+                this._postInitializedOnStartPromise = undefined;
                 // If we get a kernel promise failure, then restarting timed out. Just shutdown and restart the entire server.
                 // Note, this code might not be necessary, as such an error is thrown only when interrupting a kernel times out.
                 sendKernelTelemetryEvent(
@@ -428,7 +428,7 @@ abstract class BaseKernel implements IBaseKernel {
             this._onRestarted.fire();
 
             // Also signal that the kernel post initialization completed.
-            this._onPostInitialized.fire();
+            await this.triggerOnDidStartKernel(false, true);
         } catch (ex) {
             logger.error(`Failed to restart kernel ${getDisplayPath(this.uri)}`, ex);
             throw ex;
@@ -487,6 +487,26 @@ abstract class BaseKernel implements IBaseKernel {
         return this._jupyterSessionPromise;
     }
 
+    private async triggerOnDidStartKernel(disableUI: boolean, isRestarting = false) {
+        if (disableUI) {
+            return;
+        }
+
+        // If we started and the UI is no longer disabled (ie., a user executed a cell)
+        // then we can signal that the kernel was created and can be used by third-party extensions.
+        // We also only want to fire off a single event here.
+        if (!this._postInitializedOnStartPromise || isRestarting) {
+            this._postInitializedOnStartPromise = this._onPostInitialized.fireAsync({}, this.startCancellation.token);
+            await this._postInitializedOnStartPromise;
+        }
+
+        // Do not enable this, end up in a dead lock.
+        // E.g. extension `A` waits for `onDidStart` event, and then calls `executeCode` API.
+        // However the `executeCode` API waits for `onDidStart` event to be fired and completed, but thats still waiting for ext `A` to complete.
+        // Hence a deadlock.
+        // await this._postInitializedOnStartPromise;
+    }
+
     private async interruptExecution(
         session: IKernelSession,
         pendingExecutions: Promise<unknown>
@@ -737,6 +757,7 @@ abstract class BaseKernel implements IBaseKernel {
                         );
                         const isActiveSessionDead = this._session === session;
                         this._jupyterSessionPromise = undefined;
+                        this._postInitializedOnStartPromise = undefined;
                         this._session = undefined;
 
                         // If the active session died, then kernel is dead.
diff --git a/src/kernels/kernelExecution.ts b/src/kernels/kernelExecution.ts
index 2c27fee043c..7e32b15dcc1 100644
--- a/src/kernels/kernelExecution.ts
+++ b/src/kernels/kernelExecution.ts
@@ -166,6 +166,11 @@ export class NotebookKernelExecution implements INotebookKernelExecution {
         const sessionPromise = this.kernel.restarting.then(() => this.kernel.start(new DisplayOptions(false)));
 
         traceCellMessage(cell, `NotebookKernelExecution.executeCell (3), ${getDisplayPath(cell.notebook.uri)}`);
+
+        // Wait for the kernel to complete post initialization before queueing the cell in case
+        // we need to allow extensions to run code before the initial user-triggered execution
+        // (because of this, we intentionally do not need the same await in `executeCode`).
+        await sessionPromise;
         const executionQueue = this.getOrCreateCellExecutionQueue(cell.notebook, sessionPromise);
         executionQueue.queueCell(cell, codeOverride);
         let success = true;
@@ -196,18 +201,28 @@ export class NotebookKernelExecution implements INotebookKernelExecution {
         token: CancellationToken
     ): AsyncGenerator<NotebookCellOutput, void, unknown> {
         const stopWatch = new StopWatch();
-        // If we're restarting, wait for it to finish
-        const sessionPromise = this.kernel.restarting.then(() => this.kernel.start(new DisplayOptions(false)));
-
-        const executionQueue = this.getOrCreateCellExecutionQueue(this.notebook, sessionPromise);
 
         let result: ICodeExecution;
         if (extensionId === JVSC_EXTENSION_ID || extensionId === POWER_TOYS_EXTENSION_ID) {
+            // If we're restarting, wait for it to finish
+            // For internal extension we do not care about the UI being displayed.
+            // This is also a way to bypass the queue.
+            // If disable UI is true, then we end up triggering post execution code that results in 3rd party extensions
+            // Getting the event for kernel starting, when in fact users didn't run any code against the kernel at all.
+            // Also in those cases its possible 3rd party extensions would handle that event and then run some initialization code
+            // which in turn comes back into this and ther's a new item in the queue, but that is blocked on the previous execution.
+            // As a result we end up in a deadlock.
+            const sessionPromise = this.kernel.restarting.then(() => this.kernel.start(new DisplayOptions(true)));
+
             // No need to queue code execution for JVSC, as it will be executed immediately.
             // Only 3rd party code needs to be queued (as we need to give user code preference over 3rd party ext code)
             result = CodeExecution.fromCode(code, extensionId);
             void sessionPromise.then((session) => result.start(session));
         } else {
+            // If we're restarting, wait for it to finish
+            const sessionPromise = this.kernel.restarting.then(() => this.kernel.start(new DisplayOptions(false)));
+
+            const executionQueue = this.getOrCreateCellExecutionQueue(this.notebook, sessionPromise);
             result = executionQueue.queueCode(code, extensionId, token);
         }
         if (extensionId !== JVSC_EXTENSION_ID) {
diff --git a/src/kernels/kernelProvider.base.ts b/src/kernels/kernelProvider.base.ts
index f3dd4609bc3..38a6415752c 100644
--- a/src/kernels/kernelProvider.base.ts
+++ b/src/kernels/kernelProvider.base.ts
@@ -2,7 +2,7 @@
 // Licensed under the MIT License.
 
 import type { KernelMessage } from '@jupyterlab/services';
-import { Event, EventEmitter, NotebookDocument, Uri, workspace } from 'vscode';
+import { CancellationToken, Event, EventEmitter, NotebookDocument, Uri, workspace } from 'vscode';
 import { logger } from '../platform/logging';
 import { getDisplayPath } from '../platform/common/platform/fs-paths';
 import { IAsyncDisposable, IAsyncDisposableRegistry, IDisposableRegistry } from '../platform/common/types';
@@ -17,6 +17,7 @@ import {
     INotebookKernelExecution
 } from './types';
 import { JupyterServerProviderHandle } from './jupyter/types';
+import { AsyncEmitter } from '../platform/common/utils/events';
 
 /**
  * Provides kernels to the system. Generally backed by a URI or a notebook object.
@@ -36,7 +37,11 @@ export abstract class BaseCoreKernelProvider implements IKernelProvider {
     protected readonly _onDidCreateKernel = new EventEmitter<IKernel>();
     protected readonly _onDidDisposeKernel = new EventEmitter<IKernel>();
     protected readonly _onKernelStatusChanged = new EventEmitter<{ status: KernelMessage.Status; kernel: IKernel }>();
-    protected readonly _onDidPostInitializeKernel = new EventEmitter<IKernel>();
+    protected readonly _onDidPostInitializeKernel = new AsyncEmitter<{
+        kernel: IKernel;
+        token: CancellationToken;
+        waitUntil(thenable: Thenable<unknown>): void;
+    }>();
     public readonly onKernelStatusChanged = this._onKernelStatusChanged.event;
     public get kernels() {
         const kernels = new Set<IKernel>();
@@ -75,7 +80,11 @@ export abstract class BaseCoreKernelProvider implements IKernelProvider {
     public get onDidCreateKernel(): Event<IKernel> {
         return this._onDidCreateKernel.event;
     }
-    public get onDidPostInitializeKernel(): Event<IKernel> {
+    public get onDidPostInitializeKernel(): Event<{
+        kernel: IKernel;
+        token: CancellationToken;
+        waitUntil(thenable: Thenable<unknown>): void;
+    }> {
         return this._onDidPostInitializeKernel.event;
     }
     public get(uriOrNotebook: Uri | NotebookDocument | string): IKernel | undefined {
@@ -192,7 +201,11 @@ export abstract class BaseThirdPartyKernelProvider implements IThirdPartyKernelP
     protected readonly _onDidStartKernel = new EventEmitter<IThirdPartyKernel>();
     protected readonly _onDidCreateKernel = new EventEmitter<IThirdPartyKernel>();
     protected readonly _onDidDisposeKernel = new EventEmitter<IThirdPartyKernel>();
-    protected readonly _onDidPostInitializeKernel = new EventEmitter<IThirdPartyKernel>();
+    protected readonly _onDidPostInitializeKernel = new AsyncEmitter<{
+        kernel: IThirdPartyKernel;
+        token: CancellationToken;
+        waitUntil(thenable: Thenable<unknown>): void;
+    }>();
     protected readonly _onKernelStatusChanged = new EventEmitter<{
         status: KernelMessage.Status;
         kernel: IThirdPartyKernel;
@@ -234,7 +247,11 @@ export abstract class BaseThirdPartyKernelProvider implements IThirdPartyKernelP
     public get onDidCreateKernel(): Event<IThirdPartyKernel> {
         return this._onDidCreateKernel.event;
     }
-    public get onDidPostInitializeKernel(): Event<IThirdPartyKernel> {
+    public get onDidPostInitializeKernel(): Event<{
+        kernel: IThirdPartyKernel;
+        token: CancellationToken;
+        waitUntil(thenable: Thenable<unknown>): void;
+    }> {
         return this._onDidPostInitializeKernel.event;
     }
     public get(uri: Uri | string): IThirdPartyKernel | undefined {
diff --git a/src/kernels/kernelProvider.node.ts b/src/kernels/kernelProvider.node.ts
index 158b4b59593..b8442971e25 100644
--- a/src/kernels/kernelProvider.node.ts
+++ b/src/kernels/kernelProvider.node.ts
@@ -98,9 +98,7 @@ export class KernelProvider extends BaseCoreKernelProvider {
             this.disposables
         );
         kernel.onPostInitialized(
-            () => {
-                this._onDidPostInitializeKernel.fire(kernel);
-            },
+            (e) => e.waitUntil(this._onDidPostInitializeKernel.fireAsync({ kernel }, e.token)),
             this,
             this.disposables
         );
@@ -160,9 +158,7 @@ export class ThirdPartyKernelProvider extends BaseThirdPartyKernelProvider {
             this.disposables
         );
         kernel.onPostInitialized(
-            () => {
-                this._onDidPostInitializeKernel.fire(kernel);
-            },
+            (e) => e.waitUntil(this._onDidPostInitializeKernel.fireAsync({ kernel }, e.token)),
             this,
             this.disposables
         );
diff --git a/src/kernels/kernelProvider.node.unit.test.ts b/src/kernels/kernelProvider.node.unit.test.ts
index f5ba56cb83d..541c1aac7f3 100644
--- a/src/kernels/kernelProvider.node.unit.test.ts
+++ b/src/kernels/kernelProvider.node.unit.test.ts
@@ -5,7 +5,15 @@
 import { assert } from 'chai';
 import * as sinon from 'sinon';
 import { anything, instance, mock, when } from 'ts-mockito';
-import { EventEmitter, Memento, NotebookController, NotebookDocument, Uri } from 'vscode';
+import {
+    CancellationToken,
+    CancellationTokenSource,
+    EventEmitter,
+    Memento,
+    NotebookController,
+    NotebookDocument,
+    Uri
+} from 'vscode';
 import {
     IConfigurationService,
     IDisposable,
@@ -33,6 +41,7 @@ import { JupyterNotebookView } from '../platform/common/constants';
 import { mockedVSCodeNamespaces } from '../test/vscode-mock';
 import { CellOutputDisplayIdTracker } from './execution/cellDisplayIdTracker';
 import { IReplNotebookTrackerService } from '../platform/notebooks/replNotebookTrackerService';
+import { AsyncEmitter } from '../platform/common/utils/events';
 
 suite('Jupyter Session', () => {
     suite('Node Kernel Provider', function () {
@@ -95,7 +104,7 @@ suite('Jupyter Session', () => {
             await Promise.all(asyncDisposables.map((item) => item.dispose().catch(noop)));
             asyncDisposables.length = 0;
         });
-        function testKernelProviderEvents(thirdPartyKernelProvider = false) {
+        async function testKernelProviderEvents(thirdPartyKernelProvider = false) {
             const kernelProvider = thirdPartyKernelProvider ? create3rdPartyKernelProvider() : createKernelProvider();
             const kernelCreated = createEventHandler(kernelProvider, 'onDidCreateKernel', disposables);
             const kernelStarted = createEventHandler(kernelProvider, 'onDidStartKernel', disposables);
@@ -107,7 +116,10 @@ suite('Jupyter Session', () => {
             const onStarted = new EventEmitter<void>();
             const onStatusChanged = new EventEmitter<void>();
             const onRestartedEvent = new EventEmitter<void>();
-            const onPostInitializedEvent = new EventEmitter<void>();
+            const onPostInitializedEvent = new AsyncEmitter<{
+                token: CancellationToken;
+                waitUntil(thenable: Thenable<unknown>): void;
+            }>();
             const onDisposedEvent = new EventEmitter<void>();
             disposables.push(onStatusChanged);
             disposables.push(onRestartedEvent);
@@ -155,13 +167,13 @@ suite('Jupyter Session', () => {
             assert.isTrue(kernelStatusChanged.fired, 'IKernelProvider.onKernelStatusChanged not fired');
             onRestartedEvent.fire();
             assert.isTrue(kernelRestarted.fired, 'IKernelProvider.onKernelRestarted not fired');
-            onPostInitializedEvent.fire();
+            await onPostInitializedEvent.fireAsync({}, new CancellationTokenSource().token);
             assert.isTrue(kernelPostInitialized.fired, 'IKernelProvider.onDidPostInitializeKernel not fired');
             onDisposedEvent.fire();
             assert.isTrue(kernelDisposed.fired, 'IKernelProvider.onDisposedEvent not fired');
         }
-        test('Kernel Events', () => testKernelProviderEvents(false));
-        test('3rd Party Kernel Events', () => testKernelProviderEvents(true));
+        test('Kernel Events', async () => await testKernelProviderEvents(false));
+        test('3rd Party Kernel Events', async () => await testKernelProviderEvents(true));
     });
 
     suite('KernelProvider Node', () => {
diff --git a/src/kernels/kernelProvider.web.ts b/src/kernels/kernelProvider.web.ts
index 6a65b3f8c00..d6fdbce0433 100644
--- a/src/kernels/kernelProvider.web.ts
+++ b/src/kernels/kernelProvider.web.ts
@@ -80,7 +80,11 @@ export class KernelProvider extends BaseCoreKernelProvider {
             this.workspaceStorage
         ) as IKernel;
         kernel.onRestarted(() => this._onDidRestartKernel.fire(kernel), this, this.disposables);
-        kernel.onPostInitialized(() => this._onDidPostInitializeKernel.fire(kernel), this, this.disposables);
+        kernel.onPostInitialized(
+            (e) => e.waitUntil(this._onDidPostInitializeKernel.fireAsync({ kernel }, e.token)),
+            this,
+            this.disposables
+        );
         kernel.onDisposed(() => this._onDidDisposeKernel.fire(kernel), this, this.disposables);
         kernel.onStarted(() => this._onDidStartKernel.fire(kernel), this, this.disposables);
         kernel.onStatusChanged(
@@ -133,7 +137,11 @@ export class ThirdPartyKernelProvider extends BaseThirdPartyKernelProvider {
             this.workspaceStorage
         );
         kernel.onRestarted(() => this._onDidRestartKernel.fire(kernel), this, this.disposables);
-        kernel.onPostInitialized(() => this._onDidPostInitializeKernel.fire(kernel), this, this.disposables);
+        kernel.onPostInitialized(
+            (e) => e.waitUntil(this._onDidPostInitializeKernel.fireAsync({ kernel }, e.token)),
+            this,
+            this.disposables
+        );
         kernel.onDisposed(() => this._onDidDisposeKernel.fire(kernel), this, this.disposables);
         kernel.onStarted(() => this._onDidStartKernel.fire(kernel), this, this.disposables);
         kernel.onStatusChanged(
diff --git a/src/kernels/kernelProvider.web.unit.test.ts b/src/kernels/kernelProvider.web.unit.test.ts
index 6c8cc09cda2..f0a3ee42085 100644
--- a/src/kernels/kernelProvider.web.unit.test.ts
+++ b/src/kernels/kernelProvider.web.unit.test.ts
@@ -5,7 +5,7 @@
 import { assert } from 'chai';
 import * as sinon from 'sinon';
 import { anything, instance, mock, when } from 'ts-mockito';
-import { EventEmitter, Memento } from 'vscode';
+import { CancellationToken, CancellationTokenSource, EventEmitter, Memento } from 'vscode';
 import { IConfigurationService, IDisposable, IExtensionContext } from '../platform/common/types';
 import { createEventHandler } from '../test/common';
 import { createKernelController, TestNotebookDocument } from '../test/datascience/notebook/executionHelper';
@@ -16,6 +16,7 @@ import { IKernelSessionFactory, IKernelController, IStartupCodeProviders, Kernel
 import { ThirdPartyKernelProvider } from './kernelProvider.node';
 import { dispose } from '../platform/common/utils/lifecycle';
 import { noop } from '../test/core';
+import { AsyncEmitter } from '../platform/common/utils/events';
 
 suite('Jupyter Session', () => {
     suite('Web Kernel Provider', function () {
@@ -76,7 +77,7 @@ suite('Jupyter Session', () => {
             await Promise.all(asyncDisposables.map((item) => item.dispose().catch(noop)));
             asyncDisposables.length = 0;
         });
-        function testKernelProviderEvents(thirdPartyKernelProvider = false) {
+        async function testKernelProviderEvents(thirdPartyKernelProvider = false) {
             const kernelProvider = thirdPartyKernelProvider ? create3rdPartyKernelProvider() : createKernelProvider();
             const kernelCreated = createEventHandler(kernelProvider, 'onDidCreateKernel', disposables);
             const kernelStarted = createEventHandler(kernelProvider, 'onDidStartKernel', disposables);
@@ -88,7 +89,10 @@ suite('Jupyter Session', () => {
             const onStarted = new EventEmitter<void>();
             const onStatusChanged = new EventEmitter<void>();
             const onRestartedEvent = new EventEmitter<void>();
-            const onPostInitializedEvent = new EventEmitter<void>();
+            const onPostInitializedEvent = new AsyncEmitter<{
+                token: CancellationToken;
+                waitUntil(thenable: Thenable<unknown>): void;
+            }>();
             const onDisposedEvent = new EventEmitter<void>();
             disposables.push(onStatusChanged);
             disposables.push(onRestartedEvent);
@@ -136,12 +140,12 @@ suite('Jupyter Session', () => {
             assert.isTrue(kernelStatusChanged.fired, 'IKernelProvider.onKernelStatusChanged not fired');
             onRestartedEvent.fire();
             assert.isTrue(kernelRestarted.fired, 'IKernelProvider.onKernelRestarted not fired');
-            onPostInitializedEvent.fire();
+            await onPostInitializedEvent.fireAsync({}, new CancellationTokenSource().token);
             assert.isTrue(kernelPostInitialized.fired, 'IKernelProvider.onDidPostInitializeKernel not fired');
             onDisposedEvent.fire();
             assert.isTrue(kernelDisposed.fired, 'IKernelProvider.onDisposedEvent not fired');
         }
-        test('Kernel Events', () => testKernelProviderEvents(false));
-        test('3rd Party Kernel Events', () => testKernelProviderEvents(true));
+        test('Kernel Events', async () => await testKernelProviderEvents(false));
+        test('3rd Party Kernel Events', async () => await testKernelProviderEvents(true));
     });
 });
diff --git a/src/kernels/types.ts b/src/kernels/types.ts
index b9bc32cf8a4..7dfd9f78a80 100644
--- a/src/kernels/types.ts
+++ b/src/kernels/types.ts
@@ -355,7 +355,7 @@ export interface IBaseKernel extends IAsyncDisposable {
     readonly onDisposed: Event<void>;
     readonly onStarted: Event<void>;
     readonly onRestarted: Event<void>;
-    readonly onPostInitialized: Event<void>;
+    readonly onPostInitialized: Event<{ token: CancellationToken; waitUntil(thenable: Thenable<unknown>): void }>;
     readonly restarting: Promise<void>;
     readonly status: KernelMessage.Status;
     readonly disposed: boolean;
@@ -513,7 +513,11 @@ export interface IBaseKernelProvider<T extends IBaseKernel> extends IAsyncDispos
     onDidRestartKernel: Event<T>;
     onDidDisposeKernel: Event<T>;
     onKernelStatusChanged: Event<{ status: KernelMessage.Status; kernel: T }>;
-    onDidPostInitializeKernel: Event<T>;
+    onDidPostInitializeKernel: Event<{
+        kernel: T;
+        token: CancellationToken;
+        waitUntil(thenable: Thenable<unknown>): void;
+    }>;
 }
 
 /**
diff --git a/src/platform/common/constants.ts b/src/platform/common/constants.ts
index 79b04f69ad9..ccceaa13805 100644
--- a/src/platform/common/constants.ts
+++ b/src/platform/common/constants.ts
@@ -381,6 +381,7 @@ export enum Telemetry {
     NewJupyterKernelApiUsage = 'DATASCIENCE.JUPYTER_NEW_KERNEL_API_USAGE',
     NewJupyterKernelsApiUsage = 'DATASCIENCE.JUPYTER_NEW_KERNELS_API_USAGE',
     NewJupyterKernelApiExecution = 'DATASCIENCE.JUPYTER_NEW_KERNEL_API_EXEC',
+    NewJupyterKernelApiKernelStartupWaitUntil = 'DATASCIENCE.JUPYTER_NEW_KERNEL_API_KERNEL_STARTUP_WAIT_UNTIL',
     JupyterKernelApiAccess = 'DATASCIENCE.JUPYTER_KERNEL_API_ACCESS',
     JupyterKernelStartupHook = 'DATASCIENCE.JUPYTER_KERNEL_STARTUP_HOOK',
     JupyterKernelSpecEnumeration = 'DATASCIENCE.JUPYTER_KERNEL_SPEC_FETCH_FAILURE',
diff --git a/src/platform/common/utils/events.ts b/src/platform/common/utils/events.ts
index a84cd13eed6..2021ca74120 100644
--- a/src/platform/common/utils/events.ts
+++ b/src/platform/common/utils/events.ts
@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
-import type { Event } from 'vscode';
+import { CancellationToken, Disposable, Event } from 'vscode';
 import { IDisposable } from '../types';
 import { EmptyDisposable } from './lifecycle';
 
@@ -47,3 +47,81 @@ export function toPromise<T>(event: Event<T>, thisArgs: any = null, disposables?
 
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 export const EmptyEvent: Event<any> = () => EmptyDisposable;
+
+export interface IWaitUntil {
+    token: CancellationToken;
+    waitUntil(thenable: Promise<unknown>): void;
+}
+export type IWaitUntilData<T> = Omit<Omit<T, 'waitUntil'>, 'token'>;
+
+// Based on AsyncEmitter in https://github.com/microsoft/vscode/blob/88e6face01795b161523824ba075444fad55466a/src/vs/base/common/event.ts#L1303
+export class AsyncEmitter<T extends IWaitUntil> {
+    private _listeners: Set<(e: T) => unknown> = new Set();
+    private _asyncDeliveryQueue?: Array<[(ev: T) => void, IWaitUntilData<T>]>;
+    private _event: Event<T> | undefined;
+
+    public get event(): Event<T> {
+        if (!this._event) {
+            this._event = (listener: (e: T) => unknown, thisArg?: unknown, disposables?: Disposable[]): Disposable => {
+                this._listeners.add(thisArg ? listener.bind(thisArg) : listener);
+                const disposable = new Disposable(() => this._listeners.delete(listener));
+                disposables?.push(disposable);
+                return disposable;
+            };
+        }
+        return this._event;
+    }
+
+    async fireAsync(data: IWaitUntilData<T>, token: CancellationToken): Promise<void> {
+        if (!this._listeners) {
+            return;
+        }
+
+        if (!this._asyncDeliveryQueue) {
+            this._asyncDeliveryQueue = [];
+        }
+
+        for (const listener of this._listeners) {
+            this._asyncDeliveryQueue!.push([listener, data]);
+        }
+
+        while (this._asyncDeliveryQueue.length > 0 && !token.isCancellationRequested) {
+            const [listener, data] = this._asyncDeliveryQueue.shift()!;
+            const thenables: Promise<unknown>[] = [];
+
+            const event = <T>{
+                ...data,
+                token,
+                waitUntil: (p: Promise<unknown>): void => {
+                    if (Object.isFrozen(thenables)) {
+                        throw new Error('waitUntil can NOT be called asynchronous');
+                    }
+                    thenables.push(p);
+                }
+            };
+
+            try {
+                listener(event);
+            } catch (e) {
+                console.error(e);
+                continue;
+            }
+
+            // freeze thenables-collection to enforce sync-calls to
+            // wait until and then wait for all thenables to resolve
+            Object.freeze(thenables);
+
+            await Promise.allSettled(thenables).then((values) => {
+                for (const value of values) {
+                    if (value.status === 'rejected') {
+                        console.error(value.reason);
+                    }
+                }
+            });
+        }
+    }
+
+    dispose(): void {
+        this._listeners.clear();
+    }
+}
diff --git a/src/platform/common/utils/events.unit.test.ts b/src/platform/common/utils/events.unit.test.ts
new file mode 100644
index 00000000000..1d7e7814230
--- /dev/null
+++ b/src/platform/common/utils/events.unit.test.ts
@@ -0,0 +1,237 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+import { assert } from 'chai';
+import * as sinon from 'sinon';
+import { AsyncEmitter, IWaitUntil } from './events';
+import * as fakeTimers from '@sinonjs/fake-timers';
+import { Disposable, CancellationTokenSource } from 'vscode';
+import { IDisposable } from '../types';
+import { dispose } from './lifecycle';
+import { createDeferredFromPromise } from './async';
+
+suite('AsyncEmitter', async () => {
+    let clock: fakeTimers.InstalledClock;
+    let disposables: IDisposable[] = [];
+
+    const timeout = (timeout: number) => new Promise((resolve) => setTimeout(resolve, timeout));
+
+    setup(() => {
+        clock = fakeTimers.install();
+        console.error = sinon.stub(); // Errors in AsyncEmitter are logged, so we can suppress them here.
+        disposables.push(new Disposable(() => clock.uninstall()));
+    });
+
+    teardown(() => {
+        sinon.restore();
+        disposables = dispose(disposables);
+    });
+
+    test('event has waitUntil-function', async function () {
+        let called = false;
+
+        interface E extends IWaitUntil {
+            foo: boolean;
+            bar: number;
+        }
+
+        const emitter = new AsyncEmitter<E>();
+        disposables.push(emitter);
+        disposables.push(
+            emitter.event((e) => {
+                called = true;
+                assert.strictEqual(e.foo, true);
+                assert.strictEqual(e.bar, 1);
+                assert.strictEqual(typeof e.waitUntil, 'function');
+            })
+        );
+
+        await emitter.fireAsync({ foo: true, bar: 1 }, new CancellationTokenSource().token);
+        assert.strictEqual(called, true);
+    });
+
+    test('sequential delivery', async () => {
+        interface E extends IWaitUntil {
+            foo: boolean;
+        }
+
+        let globalState = 0;
+        const emitter = new AsyncEmitter<E>();
+        disposables.push(emitter);
+        disposables.push(
+            emitter.event((e) => {
+                e.waitUntil(
+                    timeout(10).then((_) => {
+                        assert.strictEqual(globalState, 0);
+                        globalState += 1;
+                    })
+                );
+            })
+        );
+        disposables.push(
+            emitter.event((e) => {
+                e.waitUntil(
+                    timeout(1).then((_) => {
+                        assert.strictEqual(globalState, 1);
+                        globalState += 1;
+                    })
+                );
+            })
+        );
+
+        void clock.tickAsync(100);
+        await emitter.fireAsync({ foo: true }, new CancellationTokenSource().token);
+        assert.strictEqual(globalState, 2);
+    });
+
+    test('sequential, in-order delivery', async function () {
+        interface E extends IWaitUntil {
+            foo: number;
+        }
+        const events: number[] = [];
+        let done = false;
+        const emitter = new AsyncEmitter<E>();
+        disposables.push(emitter);
+
+        // e1
+        disposables.push(
+            emitter.event((e) => {
+                e.waitUntil(
+                    timeout(10).then(async (_) => {
+                        if (e.foo === 1) {
+                            await emitter.fireAsync({ foo: 2 }, new CancellationTokenSource().token);
+                            assert.deepStrictEqual(events, [1, 2]);
+                            done = true;
+                        }
+                    })
+                );
+            })
+        );
+
+        // e2
+        disposables.push(
+            emitter.event((e) => {
+                events.push(e.foo);
+                e.waitUntil(timeout(7));
+            })
+        );
+
+        void clock.tickAsync(100);
+        await emitter.fireAsync({ foo: 1 }, new CancellationTokenSource().token);
+        assert.ok(done);
+    });
+
+    test('sequential, in-order delivery with proxied event emitter', async function () {
+        interface E extends IWaitUntil {
+            foo: number;
+        }
+        const events: Array<{ foo: number; bar: number }> = [];
+        let done = false;
+        const emitter = new AsyncEmitter<E>();
+        disposables.push(emitter);
+
+        let bar = 0;
+        // set up emitter 2 as a proxied event emitter with an additional param
+        const emitter2 = new AsyncEmitter<{ bar: number } & E>();
+        disposables.push(emitter2);
+        disposables.push(emitter.event((e) => e.waitUntil(emitter2.fireAsync({ foo: e.foo, bar: bar++ }, e.token))));
+
+        // e1
+        disposables.push(
+            emitter2.event((e) => {
+                e.waitUntil(
+                    timeout(10).then(async (_) => {
+                        if (e.foo === 1) {
+                            await emitter.fireAsync({ foo: 2 }, new CancellationTokenSource().token);
+                            assert.deepStrictEqual(events, [
+                                { foo: 1, bar: 0 },
+                                { foo: 2, bar: 1 }
+                            ]);
+                            done = true;
+                        }
+                    })
+                );
+            })
+        );
+
+        // e2
+        disposables.push(
+            emitter2.event((e) => {
+                events.push({ foo: e.foo, bar: e.bar });
+                e.waitUntil(timeout(7));
+            })
+        );
+
+        const deferrable = createDeferredFromPromise(
+            emitter.fireAsync({ foo: 1 }, new CancellationTokenSource().token)
+        );
+
+        // time: 9
+        await clock.tickAsync(9);
+        assert.deepStrictEqual(events, []);
+        assert.strictEqual(deferrable.resolved, false);
+
+        // time: 10 (e1 is unblocked, so e2 runs)
+        await clock.tickAsync(1);
+        assert.deepStrictEqual(events, [{ foo: 1, bar: 0 }]);
+        assert.strictEqual(deferrable.resolved, false);
+
+        // time: 17 (e2 is unblocked so second fireAsync can run)
+        await clock.tickAsync(7);
+        assert.deepStrictEqual(events, [{ foo: 1, bar: 0 }]);
+        assert.strictEqual(deferrable.resolved, false);
+
+        // time: 27 (e2 is unblocked again)
+        await clock.tickAsync(10);
+        assert.deepStrictEqual(events, [
+            { foo: 1, bar: 0 },
+            { foo: 2, bar: 1 }
+        ]);
+        assert.strictEqual(deferrable.resolved, false);
+
+        // time: 34 (second fireAsync resolves)
+        await clock.tickAsync(7);
+        assert.deepStrictEqual(events, [
+            { foo: 1, bar: 0 },
+            { foo: 2, bar: 1 }
+        ]);
+
+        // make sure that the fireAsync from the parent resolves at this point
+        assert.strictEqual(deferrable.resolved, true);
+        assert.ok(done);
+    });
+
+    test('catch errors', async function () {
+        interface E extends IWaitUntil {
+            foo: boolean;
+        }
+
+        let globalState = 0;
+        const emitter = new AsyncEmitter<E>();
+        disposables.push(emitter);
+        disposables.push(
+            emitter.event((e) => {
+                globalState += 1;
+                e.waitUntil(new Promise((_r, reject) => reject(new Error())));
+            })
+        );
+        disposables.push(
+            emitter.event((e) => {
+                globalState += 1;
+                e.waitUntil(timeout(10));
+                e.waitUntil(timeout(20).then(() => globalState++)); // multiple `waitUntil` are supported and awaited on
+            })
+        );
+
+        void clock.tickAsync(100);
+        await emitter
+            .fireAsync({ foo: true }, new CancellationTokenSource().token)
+            .then(() => {
+                assert.strictEqual(globalState, 3);
+            })
+            .catch((e) => {
+                console.log(e);
+                assert.ok(false);
+            });
+    });
+});
diff --git a/src/standalone/api/kernels/api.vscode.common.test.ts b/src/standalone/api/kernels/api.vscode.common.test.ts
index 9236e2e68ff..439899b0129 100644
--- a/src/standalone/api/kernels/api.vscode.common.test.ts
+++ b/src/standalone/api/kernels/api.vscode.common.test.ts
@@ -268,35 +268,41 @@ suiteMandatory('Kernel API Tests @typescript', function () {
             // Register event listener to track invocations
             const source = new CancellationTokenSource();
             let startEventCounter = 0;
+
+            const executionOrderSet = createDeferred();
             disposables.push(
-                kernels.onDidStart(async ({ kernel }) => {
-                    const codeToRun =
-                        startEventCounter === 0 ? `let foo = ${startEventCounter}` : `foo = ${startEventCounter}`;
-                    startEventCounter++;
-
-                    // This is needed for the async generator to get executed.
-                    // eslint-disable-next-line @typescript-eslint/no-unused-vars
-                    for await (const _out of kernel.executeCode(codeToRun, source.token)) {
-                    }
+                kernels.onDidStart(async ({ kernel, waitUntil }) => {
+                    waitUntil(
+                        (async () => {
+                            const codeToRun =
+                                startEventCounter === 0
+                                    ? `let foo = ${startEventCounter}`
+                                    : `foo = ${startEventCounter}`;
+                            startEventCounter++;
+
+                            // This is needed for the async generator to get executed.
+                            // eslint-disable-next-line @typescript-eslint/no-unused-vars
+                            for await (const _out of kernel.executeCode(codeToRun, source.token)) {
+                            }
+
+                            // Cell should not have executed at this point.
+                            assert.strictEqual(executionOrderSet.resolved, false);
+                        })()
+                    );
                 })
             );
             await insertCodeCell('console.log(foo)', { index: 0, language: 'typescript' });
 
-            await realKernel.start({
-                disableUI: true,
-                onDidChangeDisableUI: () => ({
-                    dispose: noop
-                })
-            });
             assert.equal(startEventCounter, 0, 'Kernel start event was triggered for a non-user kernel start');
             const cell = notebook.cellAt(0)!;
-            const executionOrderSet = createDeferred();
             const eventHandler = notebookCellExecutions.onDidChangeNotebookCellExecutionState((e) => {
                 if (e.cell === cell && e.cell.executionSummary?.executionOrder) {
                     executionOrderSet.resolve();
                 }
             });
             disposables.push(eventHandler);
+
+            // Do not explicitly start the kernel here, let it be triggered by the cell execution.
             await Promise.all([runCell(cell), waitForExecutionCompletedSuccessfully(cell), executionOrderSet.promise]);
 
             // Validate the cell execution output is equal to the expected value of "foo = 0"
diff --git a/src/standalone/api/kernels/backgroundExecution.ts b/src/standalone/api/kernels/backgroundExecution.ts
index 04e8659e5bb..5732de0b955 100644
--- a/src/standalone/api/kernels/backgroundExecution.ts
+++ b/src/standalone/api/kernels/backgroundExecution.ts
@@ -19,7 +19,7 @@ export async function execCodeInBackgroundThread<T>(
 ) {
     const counter = executionCounters.get(kernel) || 0;
     executionCounters.set(kernel, counter + 1);
-    const api = createKernelApiForExtension(JVSC_EXTENSION_ID, kernel);
+    const { api } = createKernelApiForExtension(JVSC_EXTENSION_ID, kernel);
     const mime = `application/vnd.vscode.bg.execution.${counter}`;
     const mimeFinalResult = `application/vnd.vscode.bg.execution.${counter}.result`;
     const mimeErrorResult = `application/vnd.vscode.bg.execution.${counter}.error`;
diff --git a/src/standalone/api/kernels/index.ts b/src/standalone/api/kernels/index.ts
index b84065cb414..47bc4f8bcf1 100644
--- a/src/standalone/api/kernels/index.ts
+++ b/src/standalone/api/kernels/index.ts
@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
-import { Uri, workspace, EventEmitter } from 'vscode';
+import { Uri, workspace, EventEmitter, CancellationToken } from 'vscode';
 import { Kernel, Kernels } from '../../../api';
 import { ServiceContainer } from '../../../platform/ioc/container';
 import { IKernel, IKernelProvider } from '../../../kernels/types';
@@ -10,13 +10,43 @@ import { Telemetry, sendTelemetryEvent } from '../../../telemetry';
 import { DATA_WRANGLER_EXTENSION_ID, JVSC_EXTENSION_ID } from '../../../platform/common/constants';
 import { initializeInteractiveOrNotebookTelemetryBasedOnUserAction } from '../../../kernels/telemetry/helper';
 import { IDisposableRegistry } from '../../../platform/common/types';
+import { createDeferredFromPromise } from '../../../platform/common/utils/async';
+import { logger } from '../../../platform/logging';
+import { StopWatch } from '../../../platform/common/utils/stopWatch';
+import { sendKernelTelemetryEvent } from '../../../kernels/telemetry/sendKernelTelemetryEvent';
+import { KernelExecutionProgressIndicator } from './kernelProgressIndicator';
 
-const kernelCache = new WeakMap<IKernel, Kernel>();
-let _onDidStart: EventEmitter<{ uri: Uri; kernel: Kernel }> | undefined = undefined;
+const extensionAPICache = new Map<
+    string,
+    {
+        onDidStart:
+            | EventEmitter<{
+                  uri: Uri;
+                  kernel: Kernel;
+                  token: CancellationToken;
+                  waitUntil(thenable: Thenable<unknown>): void;
+              }>
+            | undefined;
+        // Kernel cache needs to be scoped per extension to make sure that the progress messages
+        // show accurately which extension is actually using it.
+        kernels: WeakMap<IKernel, { api: Kernel; progress: KernelExecutionProgressIndicator }>;
+    }
+>();
+
+function getOrCreateExtensionAPI(extensionId: string) {
+    if (!extensionAPICache.has(extensionId)) {
+        extensionAPICache.set(extensionId, {
+            onDidStart: undefined,
+            kernels: new WeakMap<IKernel, { api: Kernel; progress: KernelExecutionProgressIndicator }>()
+        });
+    }
+    return extensionAPICache.get(extensionId)!;
+}
 
 function getWrappedKernel(kernel: IKernel, extensionId: string) {
-    let wrappedKernel = kernelCache.get(kernel) || createKernelApiForExtension(extensionId, kernel);
-    kernelCache.set(kernel, wrappedKernel);
+    const extensionAPI = getOrCreateExtensionAPI(extensionId);
+    let wrappedKernel = extensionAPI.kernels.get(kernel) || createKernelApiForExtension(extensionId, kernel);
+    extensionAPI.kernels.set(kernel, wrappedKernel);
     return wrappedKernel;
 }
 
@@ -44,7 +74,8 @@ export function getKernelsApi(extensionId: string): Kernels {
                     kernel.kernelConnectionMetadata
                 );
             }
-            return getWrappedKernel(kernel, extensionId);
+            const { api } = getWrappedKernel(kernel, extensionId);
+            return api;
         },
         get onDidStart() {
             if (![JVSC_EXTENSION_ID, DATA_WRANGLER_EXTENSION_ID].includes(extensionId)) {
@@ -52,21 +83,54 @@ export function getKernelsApi(extensionId: string): Kernels {
             }
 
             // We can cache the event emitter for subsequent calls.
-            if (!_onDidStart) {
+            const extensionAPI = getOrCreateExtensionAPI(extensionId);
+            if (!extensionAPI.onDidStart) {
                 const kernelProvider = ServiceContainer.instance.get<IKernelProvider>(IKernelProvider);
                 const disposableRegistry = ServiceContainer.instance.get<IDisposableRegistry>(IDisposableRegistry);
-                _onDidStart = new EventEmitter<{ uri: Uri; kernel: Kernel }>();
+                extensionAPI.onDidStart = new EventEmitter<{
+                    uri: Uri;
+                    kernel: Kernel;
+                    token: CancellationToken;
+                    waitUntil(thenable: Thenable<unknown>): void;
+                }>();
 
                 disposableRegistry.push(
-                    kernelProvider.onDidPostInitializeKernel((kernel) => {
-                        _onDidStart?.fire({ uri: kernel.uri, kernel: getWrappedKernel(kernel, extensionId) });
+                    extensionAPI.onDidStart,
+                    kernelProvider.onDidPostInitializeKernel(({ kernel, token, waitUntil }) => {
+                        const { api, progress } = getWrappedKernel(kernel, extensionId);
+                        extensionAPI.onDidStart?.fire({
+                            uri: kernel.uri,
+                            kernel: api,
+                            token,
+                            waitUntil: (thenable) => {
+                                // Wrap around the `waitUntil` method to inject telemetry and notifications.
+                                // For notifications, we reuse the kernel execution progress indicator message
+                                // regardless of whether something is actually running on the kernel, since
+                                // it is effectively preventing access to it.
+                                const deferrable = createDeferredFromPromise(Promise.resolve(thenable));
+                                waitUntil(thenable);
+                                const disposable = progress.show();
+                                const stopWatch = new StopWatch();
+                                void deferrable.promise.finally(() => {
+                                    logger.trace(
+                                        `${extensionId} took ${stopWatch.elapsedTime}ms during kernel startup`
+                                    );
+                                    sendKernelTelemetryEvent(
+                                        kernel.resourceUri,
+                                        Telemetry.NewJupyterKernelApiKernelStartupWaitUntil,
+                                        { duration: stopWatch.elapsedTime },
+                                        { extensionId }
+                                    );
+                                    disposable.dispose();
+                                });
+                            }
+                        });
                     }),
-                    _onDidStart,
-                    { dispose: () => (_onDidStart = undefined) }
+                    extensionAPI.onDidStart
                 );
             }
 
-            return _onDidStart.event;
+            return extensionAPI.onDidStart.event;
         }
     };
 }
diff --git a/src/standalone/api/kernels/kernel.ts b/src/standalone/api/kernels/kernel.ts
index efb1cb962d7..2e74d0dbf02 100644
--- a/src/standalone/api/kernels/kernel.ts
+++ b/src/standalone/api/kernels/kernel.ts
@@ -3,32 +3,17 @@
 
 /* eslint-disable @typescript-eslint/no-explicit-any */
 
-import {
-    l10n,
-    CancellationToken,
-    ProgressLocation,
-    extensions,
-    window,
-    Disposable,
-    workspace,
-    NotebookDocument,
-    Event,
-    EventEmitter,
-    NotebookCellOutput,
-    type NotebookExecution,
-    type NotebookController
-} from 'vscode';
+import { l10n, CancellationToken, Event, EventEmitter, NotebookCellOutput, type NotebookController } from 'vscode';
 import { Kernel, KernelStatus, Output } from '../../../api';
 import { ServiceContainer } from '../../../platform/ioc/container';
 import { IKernel, IKernelProvider, INotebookKernelExecution } from '../../../kernels/types';
-import { getDisplayNameOrNameOfKernelConnection, isPythonKernelConnection } from '../../../kernels/helpers';
+import { isPythonKernelConnection } from '../../../kernels/helpers';
 import { IDisposable, IDisposableRegistry } from '../../../platform/common/types';
-import { DisposableBase, ReferenceCollection, dispose } from '../../../platform/common/utils/lifecycle';
+import { DisposableBase, dispose } from '../../../platform/common/utils/lifecycle';
 import { noop } from '../../../platform/common/utils/misc';
 import { getTelemetrySafeHashedString } from '../../../platform/telemetry/helpers';
 import { Telemetry, sendTelemetryEvent } from '../../../telemetry';
 import { StopWatch } from '../../../platform/common/utils/stopWatch';
-import { Deferred, createDeferred, sleep } from '../../../platform/common/utils/async';
 import { once } from '../../../platform/common/utils/events';
 import { logger } from '../../../platform/logging';
 import {
@@ -45,133 +30,7 @@ import {
 import { getNotebookCellOutputMetadata } from '../../../kernels/execution/helpers';
 import { registerChangeHandler, requestApiAccess } from './apiAccess';
 import { IControllerRegistration } from '../../../notebooks/controllers/types';
-
-class NotebookExecutionReferenceCollection extends ReferenceCollection<NotebookExecution> {
-    private existingExecutions?: NotebookExecution;
-    constructor(
-        private readonly controller: NotebookController,
-        private readonly notebook: NotebookDocument
-    ) {
-        super();
-    }
-    public dispose() {
-        this.disposeExistingExecution();
-    }
-
-    protected override createReferencedObject(_key: string, ..._args: any[]): NotebookExecution {
-        if (!this.existingExecutions) {
-            this.existingExecutions = this.controller.createNotebookExecution(this.notebook);
-            this.existingExecutions.start();
-        }
-        return this.existingExecutions;
-    }
-    protected override destroyReferencedObject(_key: string, _object: NotebookExecution): void {
-        this.disposeExistingExecution();
-    }
-    private disposeExistingExecution() {
-        try {
-            this.existingExecutions?.end();
-        } catch {
-            //
-        }
-        this.existingExecutions = undefined;
-    }
-}
-/**
- * Displays a progress indicator when 3rd party extensions execute code against a kernel.
- * The progress indicator is displayed only when the notebook is visible.
- *
- * We need this to notify users when execution takes place for:
- * 1. Transparency (they might not know that some code is being executed in a kernel)
- * 2. If users experience delays in kernel execution within notebooks, then they have an idea why this might be the case.
- */
-class KernelExecutionProgressIndicator {
-    private readonly controllerDisplayName: string;
-    private readonly notebook?: NotebookDocument;
-    private deferred?: Deferred<void>;
-    private disposable?: IDisposable;
-    private eventHandler: IDisposable;
-    private readonly title: string;
-    private displayInProgress?: boolean;
-    private shouldDisplayProgress?: boolean;
-    private static notificationsPerExtension = new WeakMap<IKernel, Set<string>>();
-    private executionRefCountedDisposableFactory?: NotebookExecutionReferenceCollection;
-    constructor(
-        private readonly extensionId: string,
-        private readonly kernel: IKernel,
-        controller?: NotebookController
-    ) {
-        this.executionRefCountedDisposableFactory = controller
-            ? new NotebookExecutionReferenceCollection(controller, kernel.notebook)
-            : undefined;
-        const extensionDisplayName = extensions.getExtension(extensionId)?.packageJSON?.displayName || extensionId;
-        this.notebook = workspace.notebookDocuments.find((n) => n.uri.toString() === kernel.resourceUri?.toString());
-        this.controllerDisplayName = getDisplayNameOrNameOfKernelConnection(kernel.kernelConnectionMetadata);
-        this.title = l10n.t(`Executing code in {0} from {1}`, this.controllerDisplayName, extensionDisplayName);
-        this.eventHandler = window.onDidChangeVisibleNotebookEditors(this.showProgressImpl, this);
-    }
-    dispose() {
-        this.eventHandler.dispose();
-        this.disposable?.dispose();
-        this.executionRefCountedDisposableFactory?.dispose();
-    }
-
-    show() {
-        const execution = this.executionRefCountedDisposableFactory?.acquire('');
-        if (this.deferred && !this.deferred.completed) {
-            const oldDeferred = this.deferred;
-            this.deferred = createDeferred<void>();
-            oldDeferred.resolve();
-        } else {
-            this.deferred = createDeferred<void>();
-            this.showProgress().catch(noop);
-        }
-        return (this.disposable = new Disposable(() => {
-            execution?.dispose();
-            this.deferred?.resolve();
-        }));
-    }
-    private async showProgress() {
-        // Give a grace period of 1000ms to avoid displaying progress indicators too aggressively.
-        // Clearly some extensions can take a while, see here https://github.com/microsoft/vscode-jupyter/issues/15613
-        // More than 1s is too long,
-        await sleep(1_000);
-        if (!this.deferred || this.deferred.completed || this.displayInProgress) {
-            return;
-        }
-        this.shouldDisplayProgress = true;
-        await Promise.all([this.showProgressImpl(), this.waitUntilCompleted()]);
-        this.shouldDisplayProgress = false;
-    }
-    private async showProgressImpl() {
-        const notifiedExtensions =
-            KernelExecutionProgressIndicator.notificationsPerExtension.get(this.kernel) || new Set();
-        KernelExecutionProgressIndicator.notificationsPerExtension.set(this.kernel, notifiedExtensions);
-        if (notifiedExtensions.has(this.extensionId)) {
-            return;
-        }
-        notifiedExtensions.add(this.extensionId);
-        if (!this.notebook || !this.shouldDisplayProgress) {
-            return;
-        }
-        if (!window.visibleNotebookEditors.some((e) => e.notebook === this.notebook)) {
-            return;
-        }
-        this.displayInProgress = true;
-        await window.withProgress({ location: ProgressLocation.Notification, title: this.title }, async () =>
-            this.waitUntilCompleted()
-        );
-        this.displayInProgress = false;
-    }
-    private async waitUntilCompleted() {
-        let deferred = this.deferred;
-        while (deferred && !deferred.completed) {
-            await deferred.promise;
-            // Possible the deferred was replaced.
-            deferred = this.deferred;
-        }
-    }
-}
+import { KernelExecutionProgressIndicator } from './kernelProgressIndicator';
 
 /**
  * Error to be throw to to notify calls of the API that access to the API has been revoked by the user.
@@ -285,7 +144,7 @@ class WrappedKernelPerExtension extends DisposableBase implements Kernel {
     ) {
         const wrapper = new WrappedKernelPerExtension(extensionId, kernel, execution, controller);
         ServiceContainer.instance.get<IDisposableRegistry>(IDisposableRegistry).push(wrapper);
-        return wrapper._api;
+        return { api: wrapper._api, progress: wrapper.progress };
     }
 
     private async checkAccess() {
diff --git a/src/standalone/api/kernels/kernel.unit.test.ts b/src/standalone/api/kernels/kernel.unit.test.ts
index f44eb100d72..95be3ea2487 100644
--- a/src/standalone/api/kernels/kernel.unit.test.ts
+++ b/src/standalone/api/kernels/kernel.unit.test.ts
@@ -101,7 +101,7 @@ suite('Kernel Api', () => {
 
     test('Verify Access Denied error message has expected value for the property `name`', async () => {
         try {
-            const api = createKernelApiForExtension('xyz', instance(kernel));
+            const { api } = createKernelApiForExtension('xyz', instance(kernel));
             for await (const x of api.executeCode('bogus', token)) {
                 assert.fail(`Should have failed without producing any value such as ${x}`);
             }
diff --git a/src/standalone/api/kernels/kernelProgressIndicator.ts b/src/standalone/api/kernels/kernelProgressIndicator.ts
new file mode 100644
index 00000000000..aa6b5bbd2e0
--- /dev/null
+++ b/src/standalone/api/kernels/kernelProgressIndicator.ts
@@ -0,0 +1,150 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+/* eslint-disable @typescript-eslint/no-explicit-any */
+
+import {
+    Disposable,
+    extensions,
+    l10n,
+    NotebookController,
+    NotebookDocument,
+    NotebookExecution,
+    ProgressLocation,
+    window,
+    workspace
+} from 'vscode';
+import { createDeferred, Deferred, sleep } from '../../../platform/common/utils/async';
+import { IDisposable } from '../../../platform/common/types';
+import { IKernel } from '../../../kernels/types';
+import { getDisplayNameOrNameOfKernelConnection } from '../../../kernels/helpers';
+import { IReference, ReferenceCollection } from '../../../platform/common/utils/lifecycle';
+import { noop } from '../../../platform/common/utils/misc';
+
+class NotebookExecutionReferenceCollection extends ReferenceCollection<NotebookExecution> {
+    private existingExecutions?: NotebookExecution;
+    constructor(
+        private readonly controller: NotebookController,
+        private readonly notebook: NotebookDocument
+    ) {
+        super();
+    }
+    public dispose() {
+        this.disposeExistingExecution();
+    }
+
+    protected override createReferencedObject(_key: string, ..._args: any[]): NotebookExecution {
+        if (!this.existingExecutions) {
+            this.existingExecutions = this.controller.createNotebookExecution(this.notebook);
+            this.existingExecutions.start();
+        }
+        return this.existingExecutions;
+    }
+    protected override destroyReferencedObject(_key: string, _object: NotebookExecution): void {
+        this.disposeExistingExecution();
+    }
+    private disposeExistingExecution() {
+        try {
+            this.existingExecutions?.end();
+        } catch {
+            //
+        }
+        this.existingExecutions = undefined;
+    }
+}
+
+export class KernelExecutionProgressIndicator {
+    private readonly controllerDisplayName: string;
+    private readonly notebook?: NotebookDocument;
+    private deferred?: Deferred<void>;
+    private disposable?: IDisposable;
+    private eventHandler: IDisposable;
+    private readonly title: string;
+    private displayInProgress?: boolean;
+    private shouldDisplayProgress?: boolean;
+    private static notificationsPerExtension = new WeakMap<IKernel, Set<string>>();
+    private executionRefCountedDisposableFactory?: NotebookExecutionReferenceCollection;
+    constructor(
+        private readonly extensionId: string,
+        private readonly kernel: IKernel,
+        controller?: NotebookController
+    ) {
+        this.executionRefCountedDisposableFactory = controller
+            ? new NotebookExecutionReferenceCollection(controller, kernel.notebook)
+            : undefined;
+        const extensionDisplayName = extensions.getExtension(extensionId)?.packageJSON?.displayName || extensionId;
+        this.notebook = workspace.notebookDocuments.find((n) => n.uri.toString() === kernel.resourceUri?.toString());
+        this.controllerDisplayName = getDisplayNameOrNameOfKernelConnection(kernel.kernelConnectionMetadata);
+        this.title = l10n.t(`Executing code in {0} from {1}`, this.controllerDisplayName, extensionDisplayName);
+        this.eventHandler = window.onDidChangeVisibleNotebookEditors(this.showProgressImpl, this);
+    }
+    dispose() {
+        this.eventHandler.dispose();
+        this.disposable?.dispose();
+        this.executionRefCountedDisposableFactory?.dispose();
+    }
+
+    show() {
+        let execution: IReference<NotebookExecution> | undefined;
+        try {
+            execution = this.executionRefCountedDisposableFactory?.acquire('');
+        } catch {
+            // It's okay to not acquire an execution ref here as there may already be one.
+            // E.g. when user is executing a cell, then an execution is already in progress & a progress will be displayed.
+            // Hence no need to acquire another execution ref.
+        }
+
+        if (this.deferred && !this.deferred.completed) {
+            const oldDeferred = this.deferred;
+            this.deferred = createDeferred<void>();
+            oldDeferred.resolve();
+        } else {
+            this.deferred = createDeferred<void>();
+            void this.showProgress().catch(noop);
+        }
+        return (this.disposable = new Disposable(() => {
+            execution?.dispose();
+            this.deferred?.resolve();
+        }));
+    }
+    private async showProgress() {
+        // Give a grace period of 1000ms to avoid displaying progress indicators too aggressively.
+        // Clearly some extensions can take a while, see here https://github.com/microsoft/vscode-jupyter/issues/15613
+        // More than 1s is too long,
+        await sleep(1_000);
+        if (!this.deferred || this.deferred.completed || this.displayInProgress) {
+            return;
+        }
+        this.shouldDisplayProgress = true;
+        await Promise.all([this.showProgressImpl(), this.waitUntilCompleted()]);
+        this.shouldDisplayProgress = false;
+    }
+    private async showProgressImpl() {
+        const notifiedExtensions =
+            KernelExecutionProgressIndicator.notificationsPerExtension.get(this.kernel) || new Set();
+        KernelExecutionProgressIndicator.notificationsPerExtension.set(this.kernel, notifiedExtensions);
+        if (notifiedExtensions.has(this.extensionId)) {
+            return;
+        }
+        notifiedExtensions.add(this.extensionId);
+        if (!this.notebook || !this.shouldDisplayProgress) {
+            return;
+        }
+        if (!window.visibleNotebookEditors.some((e) => e.notebook === this.notebook)) {
+            return;
+        }
+        this.displayInProgress = true;
+        await window.withProgress({ location: ProgressLocation.Notification, title: this.title }, async () =>
+            this.waitUntilCompleted()
+        );
+        this.displayInProgress = false;
+    }
+    private async waitUntilCompleted() {
+        let deferred = this.deferred;
+        while (deferred && !deferred.completed) {
+            await deferred.promise;
+            // Possible the deferred was replaced.
+            deferred = this.deferred;
+        }
+    }
+}
diff --git a/src/telemetry.ts b/src/telemetry.ts
index 3ac87b3dd76..3b068db0c17 100644
--- a/src/telemetry.ts
+++ b/src/telemetry.ts
@@ -3915,6 +3915,28 @@ export class IEventNamePropertyMapping {
             }
         }
     };
+    /**
+     * Telemetry sent when an extension uses our 3rd party Kernel onDidStart API and calls waitUntil.
+     */
+    [Telemetry.NewJupyterKernelApiKernelStartupWaitUntil]: TelemetryEventInfo<
+        {
+            /**
+             * Extension Id that's attempting to use the API.
+             */
+            extensionId: string;
+        } & DurationMeasurement
+    > = {
+        owner: 'donjayamanne',
+        feature: 'N/A',
+        source: 'N/A',
+        measures: commonClassificationForDurationProperties(),
+        properties: {
+            extensionId: {
+                classification: 'PublicNonPersonalData',
+                purpose: 'FeatureInsight'
+            }
+        }
+    };
     /**
      * Telemetry sent when an extension uses our 3rd party API.
      */