diff --git a/src/kernel/dplatformhandle.cpp b/src/kernel/dplatformhandle.cpp
index ee983a6..98f9567 100644
--- a/src/kernel/dplatformhandle.cpp
+++ b/src/kernel/dplatformhandle.cpp
@@ -419,8 +419,10 @@ DPlatformHandle::DPlatformHandle(QWindow *window, QObject *parent)
 DPlatformHandle::~DPlatformHandle()
 {
 #ifndef DTK_DISABLE_TREELAND
-    g_platformThemeMap.value(this)->deleteLater();
-    g_platformThemeMap.remove(this);
+    if (auto it = g_platformThemeMap.find(this); it != g_platformThemeMap.end()) {
+        it.value()->deleteLater();
+        g_platformThemeMap.remove(it.key());
+    }
 #endif
 }
 
@@ -685,7 +687,7 @@ bool DPlatformHandle::setEnabledNoTitlebarForWindow(QWindow *window, bool enable
 
         auto handle = dPlatformWindowInterfaceByWindow(window);
         if (handle) {
-            handle->setEnabledNoTitlebar(true);
+            handle->setEnabledNoTitlebar(enable);
         }
         return true;
     }