Prevented indentation when the TAB key is pressed on a hardware keyboard during IME input

lib/src/editor/raw_editor/keyboard_shortcuts/editor_keyboard_shortcuts.dart

@@ -26,6 +26,7 @@ class EditorKeyboardShortcuts extends StatelessWidget {
     required this.controller,
     required this.readOnly,
     required this.enableAlwaysIndentOnTab,
+    required this.isImeComposingActive,
     required this.characterEvents,
     required this.spaceEvents,
     this.onKeyPressed,
@@ -36,6 +37,7 @@ class EditorKeyboardShortcuts extends StatelessWidget {
 
   final bool readOnly;
   final bool enableAlwaysIndentOnTab;
+  final bool isImeComposingActive;
   final QuillController controller;
   @experimental
   final KeyEventResult? Function(KeyEvent event, Node? node)? onKeyPressed;
@@ -78,6 +80,10 @@ class EditorKeyboardShortcuts extends StatelessWidget {
   }
 
   KeyEventResult _onKeyEvent(node, KeyEvent event) {
+    // Don't handle key if IME is active.
+    if (isImeComposingActive) {
+      return KeyEventResult.ignored;
+    }
     final onKey = onKeyPressed;
     if (onKey != null) {
       // Find the current node the user is on.

lib/src/editor/raw_editor/raw_editor_state.dart

@@ -499,6 +499,7 @@ class QuillRawEditorState extends EditorState
           controller: controller,
           readOnly: widget.config.readOnly,
           enableAlwaysIndentOnTab: widget.config.enableAlwaysIndentOnTab,
+          isImeComposingActive: isImeComposingActive,
           customShortcuts: widget.config.customShortcuts,
           customActions: widget.config.customActions,
           child: child,

lib/src/editor/raw_editor/raw_editor_state_text_input_client_mixin.dart

@@ -24,6 +24,15 @@ mixin RawEditorStateTextInputClientMixin on EditorState
     }
   }
 
+  bool get isImeComposingActive {
+    final isComposingValid =
+        _lastKnownRemoteTextEditingValue?.composing.isValid ?? false;
+    final isSelectionValid =
+        _lastKnownRemoteTextEditingValue?.selection.isValid ?? false;
+
+    return isComposingValid && isSelectionValid;
+  }
+
   TextEditingValue? get _lastKnownRemoteTextEditingValue =>
       __lastKnownRemoteTextEditingValue;