chore: fix some known issues

Author: LucasXu0

lib/appflowy_editor.dart

@@ -33,6 +33,7 @@ export 'src/render/rich_text/flowy_rich_text.dart';
 export 'src/render/selection_menu/selection_menu_widget.dart';
 export 'src/l10n/l10n.dart';
 export 'src/render/style/plugin_styles.dart';
+export 'src/render/style/editor_style.dart';
 export 'src/plugins/markdown/encoder/delta_markdown_encoder.dart';
 export 'src/plugins/markdown/encoder/document_markdown_encoder.dart';
 export 'src/plugins/markdown/encoder/parser/node_parser.dart';

lib/src/commands/command_extension.dart

@@ -57,7 +57,10 @@ extension CommandExtension on EditorState {
     Selection selection,
   ) {
     List<String> res = [];
-    if (!selection.isCollapsed) {
+    if (selection.isSingle) {
+      final plainText = textNodes.first.toPlainText();
+      res.add(plainText.substring(selection.startIndex, selection.endIndex));
+    } else if (!selection.isCollapsed) {
       for (var i = 0; i < textNodes.length; i++) {
         final plainText = textNodes[i].toPlainText();
         if (i == 0) {

lib/src/service/keyboard_service.dart

@@ -112,6 +112,7 @@ class _AppFlowyKeyboardState extends State<AppFlowyKeyboard>
     isFocus = false;
     this.showCursor = showCursor;
     _focusNode.unfocus(disposition: disposition);
+    _onFocusChange(false);
   }
 
   @override