hide list/grid viw add tab button on scroll; add snackbar margins for appbar;

app/lib/features/geckoview/features/browser/presentation/screens/browser.dart

@@ -88,21 +88,15 @@ class _AnimatedToolbar extends HookWidget {
       return null;
     }, [visible]);
 
-    final slideAnimation = useMemoized(
+    final slideAnimation = useMemoized(() {
-      () {
+      final begin = position == TabBarPosition.top
-        final begin = position == TabBarPosition.top
+          ? const Offset(0, -1)
-            ? const Offset(0, -1)
+          : const Offset(0, 1);
-            : const Offset(0, 1);
 
-        return Tween<Offset>(
+      return Tween<Offset>(begin: begin, end: Offset.zero).animate(
-          begin: begin,
+        CurvedAnimation(parent: controller, curve: Curves.easeInOutQuart),
-          end: Offset.zero,
+      );
-        ).animate(
+    }, [position]);
-          CurvedAnimation(parent: controller, curve: Curves.easeInOutQuart),
-        );
-      },
-      [position],
-    );
 
     return SlideTransition(position: slideAnimation, child: child);
   }
@@ -284,22 +278,6 @@ class BrowserScreen extends HookConsumerWidget {
       },
     );
 
-    final themeData = useMemoized(
-      () => Theme.of(context).copyWith(
-        bottomSheetTheme: BottomSheetThemeData(
-          constraints: BoxConstraints(
-            maxWidth:
-                MediaQuery.of(context).size.width -
-                math.max(
-                  MediaQuery.of(context).padding.left * 2,
-                  MediaQuery.of(context).padding.right * 2,
-                ),
-          ),
-        ),
-      ),
-      [],
-    );
-
     final pointerMoveEventsController = useStreamController<Offset>();
 
     // Watch sheet state for rendering in Stack
@@ -332,6 +310,28 @@ class BrowserScreen extends HookConsumerWidget {
     final bottomAppBarTotalHeight =
         bottomAppBarContentSize.height + bottomSafeArea;
 
+    // Theme with dynamic snackbar margin to position above bottom toolbar
+    final themeData = Theme.of(context).copyWith(
+      bottomSheetTheme: BottomSheetThemeData(
+        constraints: BoxConstraints(
+          maxWidth:
+              MediaQuery.of(context).size.width -
+              math.max(
+                MediaQuery.of(context).padding.left * 2,
+                MediaQuery.of(context).padding.right * 2,
+              ),
+        ),
+      ),
+      snackBarTheme: SnackBarThemeData(
+        behavior: SnackBarBehavior.floating,
+        insetPadding: EdgeInsets.only(
+          left: 16,
+          right: 16,
+          bottom: bottomToolbarVisible ? bottomAppBarTotalHeight + 8 : 16,
+        ),
+      ),
+    );
+
     return PopScope(
       //We need this for BackButtonListener to work downstream
       //No direct pop result will be handled here
@@ -340,6 +340,7 @@ class BrowserScreen extends HookConsumerWidget {
         data: themeData,
         child: Scaffold(
           // Minimal scaffold - only for Material overlay support (SnackBars)
+          resizeToAvoidBottomInset: false,
           body: Stack(
             children: [
               // Layer 0: Browser content (fills entire Stack - constant dimensions)
@@ -666,10 +667,7 @@ class _BrowserView extends StatelessWidget {
   final bool isFullscreen;
   final StreamSink<Offset>? pointerMoveEventSink;
 
-  const _BrowserView({
+  const _BrowserView({required this.isFullscreen, this.pointerMoveEventSink});
-    required this.isFullscreen,
-    this.pointerMoveEventSink,
-  });
 
   @override
   Widget build(BuildContext context) {

app/lib/features/geckoview/features/browser/presentation/widgets/sheets/view_tab.dart

@@ -192,6 +192,7 @@ class ViewTabSheetWidget extends HookConsumerWidget {
         controller: sheetScrollController,
         builder: (context, controller) {
           return ListView(
+            padding: EdgeInsets.zero,
             controller: controller,
             physics: const ClampingScrollPhysicsWithoutImplicit(),
             children: [

app/lib/features/geckoview/features/browser/presentation/widgets/tab_view/tab_grid_view.dart

@@ -27,7 +27,6 @@ import 'package:weblibre/features/geckoview/features/tabs/domain/repositories/co
 import 'package:weblibre/features/geckoview/features/tabs/domain/repositories/tab.dart';
 import 'package:weblibre/features/geckoview/features/tabs/domain/repositories/tab_search.dart';
 import 'package:weblibre/features/user/domain/repositories/general_settings.dart';
-import 'package:weblibre/presentation/hooks/scroll_visibility.dart';
 
 class _TabDraggable extends HookConsumerWidget {
   final TabEntity entity;
@@ -346,6 +345,7 @@ class _TabGrid extends StatelessWidget {
   Widget build(BuildContext context) {
     return GridView.builder(
       controller: scrollController,
+      padding: EdgeInsets.zero,
       gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
         //Sync values for itemHeight calculation _calculateItemHeight
         childAspectRatio: 0.75,
@@ -390,6 +390,9 @@ class ViewTabGridWidget extends HookConsumerWidget {
   final bool tabsReorderable;
   final VoidCallback onClose;
 
+  static const _hideThreshold = 0.02; // 2% of sheet size change
+  static const _showThreshold = 0.02;
+
   const ViewTabGridWidget({
     required this.onClose,
     required this.scrollController,
@@ -401,8 +404,74 @@ class ViewTabGridWidget extends HookConsumerWidget {
 
   @override
   Widget build(BuildContext context, WidgetRef ref) {
-    // Track FAB visibility based on scroll direction
+    final isFabVisible = useState(true);
-    final isFabVisible = useScrollVisibility(scrollController);
+    final lastSheetSize = useRef(0.0);
+    final isInitialized = useRef(false);
+
+    // Delay initialization to ignore initial animations
+    useEffect(() {
+      final timer = Timer(const Duration(milliseconds: 500), () {
+        isInitialized.value = true;
+        // Initialize lastSheetSize with current size
+        if (draggableScrollableController?.isAttached == true) {
+          lastSheetSize.value = draggableScrollableController!.size;
+        }
+      });
+      return timer.cancel;
+    }, []);
+
+    // Listen to DraggableScrollableController for sheet size changes
+    useEffect(() {
+      final controller = draggableScrollableController;
+      if (controller == null) return null;
+
+      void listener() {
+        if (!isInitialized.value) return;
+        if (!controller.isAttached) return;
+
+        final currentSize = controller.size;
+        final difference = currentSize - lastSheetSize.value;
+
+        // Hide when sheet expands (dragging up / scrolling down)
+        if (difference > _hideThreshold && isFabVisible.value) {
+          isFabVisible.value = false;
+        }
+        // Show when sheet collapses (dragging down / scrolling up)
+        else if (difference < -_showThreshold && !isFabVisible.value) {
+          isFabVisible.value = true;
+        }
+
+        lastSheetSize.value = currentSize;
+      }
+
+      controller.addListener(listener);
+      return () => controller.removeListener(listener);
+    }, [draggableScrollableController]);
+
+    // Fallback: Also listen to scroll controller for fullscreen mode (no draggable sheet)
+    useEffect(() {
+      if (draggableScrollableController != null) return null;
+
+      var lastOffset = 0.0;
+      void listener() {
+        if (!isInitialized.value) return;
+
+        final currentOffset = scrollController.offset;
+        final difference = currentOffset - lastOffset;
+
+        if (difference > 10.0 && isFabVisible.value) {
+          isFabVisible.value = false;
+        } else if ((difference < -10.0 || currentOffset <= 0) &&
+            !isFabVisible.value) {
+          isFabVisible.value = true;
+        }
+
+        lastOffset = currentOffset;
+      }
+
+      scrollController.addListener(listener);
+      return () => scrollController.removeListener(listener);
+    }, [scrollController, draggableScrollableController]);
 
     return Stack(
       alignment: Alignment.bottomRight,

app/lib/features/geckoview/features/browser/presentation/widgets/tab_view/tab_list_view.dart

@@ -25,7 +25,6 @@ import 'package:weblibre/features/geckoview/features/tabs/domain/repositories/co
 import 'package:weblibre/features/geckoview/features/tabs/domain/repositories/tab.dart';
 import 'package:weblibre/features/geckoview/features/tabs/domain/repositories/tab_search.dart';
 import 'package:weblibre/features/user/domain/repositories/general_settings.dart';
-import 'package:weblibre/presentation/hooks/scroll_visibility.dart';
 
 class _TabDraggable extends HookConsumerWidget {
   final TabEntity entity;
@@ -194,6 +193,7 @@ class _TabListView extends HookConsumerWidget {
         builder: (context, controller) {
           return !tabsReorderable
               ? ListView.builder(
+                  padding: EdgeInsets.zero,
                   controller: scrollController,
                   itemCount: itemCount,
                   itemExtent: _itemHeight,
@@ -359,6 +359,9 @@ class ViewTabListWidget extends HookConsumerWidget {
   final bool tabsReorderable;
   final VoidCallback onClose;
 
+  static const _hideThreshold = 0.02; // 2% of sheet size change
+  static const _showThreshold = 0.02;
+
   const ViewTabListWidget({
     required this.onClose,
     required this.scrollController,
@@ -370,8 +373,74 @@ class ViewTabListWidget extends HookConsumerWidget {
 
   @override
   Widget build(BuildContext context, WidgetRef ref) {
-    // Track FAB visibility based on scroll direction
+    final isFabVisible = useState(true);
-    final isFabVisible = useScrollVisibility(scrollController);
+    final lastSheetSize = useRef(0.0);
+    final isInitialized = useRef(false);
+
+    // Delay initialization to ignore initial animations
+    useEffect(() {
+      final timer = Timer(const Duration(milliseconds: 500), () {
+        isInitialized.value = true;
+        // Initialize lastSheetSize with current size
+        if (draggableScrollableController?.isAttached == true) {
+          lastSheetSize.value = draggableScrollableController!.size;
+        }
+      });
+      return timer.cancel;
+    }, []);
+
+    // Listen to DraggableScrollableController for sheet size changes
+    useEffect(() {
+      final controller = draggableScrollableController;
+      if (controller == null) return null;
+
+      void listener() {
+        if (!isInitialized.value) return;
+        if (!controller.isAttached) return;
+
+        final currentSize = controller.size;
+        final difference = currentSize - lastSheetSize.value;
+
+        // Hide when sheet expands (dragging up / scrolling down)
+        if (difference > _hideThreshold && isFabVisible.value) {
+          isFabVisible.value = false;
+        }
+        // Show when sheet collapses (dragging down / scrolling up)
+        else if (difference < -_showThreshold && !isFabVisible.value) {
+          isFabVisible.value = true;
+        }
+
+        lastSheetSize.value = currentSize;
+      }
+
+      controller.addListener(listener);
+      return () => controller.removeListener(listener);
+    }, [draggableScrollableController]);
+
+    // Fallback: Also listen to scroll controller for fullscreen mode (no draggable sheet)
+    useEffect(() {
+      if (draggableScrollableController != null) return null;
+
+      var lastOffset = 0.0;
+      void listener() {
+        if (!isInitialized.value) return;
+
+        final currentOffset = scrollController.offset;
+        final difference = currentOffset - lastOffset;
+
+        if (difference > 10.0 && isFabVisible.value) {
+          isFabVisible.value = false;
+        } else if ((difference < -10.0 || currentOffset <= 0) &&
+            !isFabVisible.value) {
+          isFabVisible.value = true;
+        }
+
+        lastOffset = currentOffset;
+      }
+
+      scrollController.addListener(listener);
+      return () => scrollController.removeListener(listener);
+    }, [scrollController, draggableScrollableController]);
 
     return Stack(
       alignment: Alignment.bottomRight,

app/lib/utils/ui_helper.dart

@@ -22,11 +22,9 @@ import 'package:nullability/nullability.dart';
 import 'package:url_launcher/url_launcher.dart';
 import 'package:weblibre/utils/clipboard.dart';
 
-/// Default bottom margin for floating snackbars to position above toolbar.
+/// Creates a floating snackbar.
-/// This accounts for the typical browser toolbar height.
+/// The margin is controlled by the scaffold's snackBarTheme for proper
-const _kSnackBarBottomMargin = 72.0;
+/// positioning above bottom app bars of varying heights.
-
-/// Creates a floating snackbar with proper margin for overlay toolbar layout.
 SnackBar _createFloatingSnackBar({
   required Widget content,
   Color? backgroundColor,
@@ -41,11 +39,6 @@ SnackBar _createFloatingSnackBar({
     duration: duration,
     persist: persist,
     behavior: SnackBarBehavior.floating,
-    margin: const EdgeInsets.only(
-      left: 16,
-      right: 16,
-      bottom: _kSnackBarBottomMargin,
-    ),
   );
 }