update readme

README.md

@@ -82,6 +82,7 @@ So i decided to make one myself. I did not know Dart and Flutter at all in the b
 The database itself is accessible to everyone following the important work of the Sefaria organization, so a big thank to them for that.
 
 Key features of the project:
+* the software is FREE and will be ALLWAYS FREE.
 * Built to work effeciently on any device, including Windows, Linux, and Android.
 * The app is designed to be as user friendly as possible.
 * A thorough selection process has been undertaken to ensure that the books are suitable for the Torah community

lib/screens/library_browser.dart

@@ -82,6 +82,7 @@ class _LibraryBrowserState extends State<LibraryBrowser> {
                 builder: (context, snapshot) {
                   if (snapshot.hasData) {
                     return ListView(
+                      key: PageStorageKey(currentTopCategory.toString()),
                       children: snapshot.data!,
                     );
                   }