Fix null editor handling and improve accessibility

examples/basic/src/App.tsx

@@ -20,26 +20,26 @@ export default function App() {
       <div className="container">
         <div className="editor-section">
           <div className="toolbar">
-            <button onClick={() => editor.toggleBold()} title="Bold (Cmd+B)">
+            <button onClick={() => editor?.toggleBold()} title="Bold (Cmd+B)" disabled={!editor}>
               <strong>B</strong>
             </button>
-            <button onClick={() => editor.toggleItalic()} title="Italic (Cmd+I)">
+            <button onClick={() => editor?.toggleItalic()} title="Italic (Cmd+I)" disabled={!editor}>
               <em>I</em>
             </button>
-            <button onClick={() => editor.toggleUnderline()} title="Underline (Cmd+U)">
+            <button onClick={() => editor?.toggleUnderline()} title="Underline (Cmd+U)" disabled={!editor}>
               <u>U</u>
             </button>
-            <button onClick={() => editor.toggleStrikethrough()} title="Strikethrough">
+            <button onClick={() => editor?.toggleStrikethrough()} title="Strikethrough" disabled={!editor}>
               <s>S</s>
             </button>
-            <button onClick={() => editor.toggleCode()} title="Code">
+            <button onClick={() => editor?.toggleCode()} title="Code" disabled={!editor}>
               {'</>'}
             </button>
             <span className="separator" />
-            <button onClick={() => console.log(editor.getDocument())} title="Log document to console">
+            <button onClick={() => editor && console.log(editor.getDocument())} title="Log document to console" disabled={!editor}>
               Log JSON
             </button>
-            <button onClick={() => console.log(editor.pm.state)} title="Log ProseMirror state">
+            <button onClick={() => editor && console.log(editor.pm.state)} title="Log ProseMirror state" disabled={!editor}>
               Log PM State
             </button>
           </div>

packages/react/src/components/BubbleMenu.tsx

@@ -36,9 +36,9 @@ import { ColorPicker } from './ColorPicker';
  */
 export interface BubbleMenuProps {
   /**
-   * The OpenBlockEditor instance.
+   * The OpenBlockEditor instance (can be null during initialization).
    */
-  editor: OpenBlockEditor;
+  editor: OpenBlockEditor | null;
 
   /**
    * Custom render function for the menu content.
@@ -402,6 +402,8 @@ export function BubbleMenu({
   const linkButtonRef = useRef<HTMLButtonElement>(null);
 
   useEffect(() => {
+    if (!editor || editor.isDestroyed) return;
+
     const updateState = () => {
       const state = BUBBLE_MENU_PLUGIN_KEY.getState(editor.pm.state);
       setMenuState(state ?? null);
@@ -421,26 +423,31 @@ export function BubbleMenu({
   }, [menuState?.visible]);
 
   const toggleBold = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     editor.toggleBold();
     editor.pm.view.focus();
   }, [editor]);
 
   const toggleItalic = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     editor.toggleItalic();
     editor.pm.view.focus();
   }, [editor]);
 
   const toggleUnderline = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     editor.toggleUnderline();
     editor.pm.view.focus();
   }, [editor]);
 
   const toggleStrikethrough = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     editor.toggleStrikethrough();
     editor.pm.view.focus();
   }, [editor]);
 
   const toggleCode = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     editor.toggleCode();
     editor.pm.view.focus();
   }, [editor]);
@@ -453,7 +460,7 @@ export function BubbleMenu({
     setShowLinkPopover(false);
   }, []);
 
-  if (!menuState?.visible || !menuState.coords) {
+  if (!editor || editor.isDestroyed || !menuState?.visible || !menuState.coords) {
     return null;
   }
 

packages/react/src/components/OpenBlockView.tsx

@@ -28,9 +28,9 @@ import { OpenBlockEditor } from '@labbs/openblock-core';
  */
 export interface OpenBlockViewProps {
   /**
-   * The OpenBlockEditor instance to render
+   * The OpenBlockEditor instance to render (can be null during initialization)
    */
-  editor: OpenBlockEditor;
+  editor: OpenBlockEditor | null;
 
   /**
    * Additional class name(s) for the container
@@ -58,9 +58,9 @@ export interface OpenBlockViewRef {
   container: HTMLDivElement | null;
 
   /**
-   * The OpenBlockEditor instance
+   * The OpenBlockEditor instance (can be null during initialization)
    */
-  editor: OpenBlockEditor;
+  editor: OpenBlockEditor | null;
 }
 
 /**

packages/react/src/components/SlashMenu.tsx

@@ -37,9 +37,9 @@ import {
  */
 export interface SlashMenuProps {
   /**
-   * The OpenBlockEditor instance.
+   * The OpenBlockEditor instance (can be null during initialization).
    */
-  editor: OpenBlockEditor;
+  editor: OpenBlockEditor | null;
 
   /**
    * Custom menu items (optional).
@@ -121,12 +121,14 @@ export function SlashMenu({
   const [openUpward, setOpenUpward] = useState(false);
   const menuRef = useRef<HTMLDivElement>(null);
 
-  // Get menu items
-  const allItems = customItems ?? getDefaultSlashMenuItems(editor.pm.state.schema);
+  // Get menu items (only when editor is available)
+  const allItems = editor ? (customItems ?? getDefaultSlashMenuItems(editor.pm.state.schema)) : [];
   const filteredItems = menuState ? filterSlashMenuItems(allItems, menuState.query) : [];
 
   // Subscribe to plugin state changes
   useEffect(() => {
+    if (!editor || editor.isDestroyed) return;
+
     const updateState = () => {
       const state = SLASH_MENU_PLUGIN_KEY.getState(editor.pm.state);
       setMenuState(state ?? null);
@@ -143,7 +145,7 @@ export function SlashMenu({
 
   // Handle keyboard navigation
   useEffect(() => {
-    if (!menuState?.active) return;
+    if (!editor || editor.isDestroyed || !menuState?.active) return;
 
     const handleKeyDown = (event: KeyboardEvent) => {
       switch (event.key) {
@@ -175,7 +177,7 @@ export function SlashMenu({
   // Handle item selection
   const handleSelect = useCallback(
     (item: SlashMenuItem) => {
-      if (!menuState) return;
+      if (!editor || editor.isDestroyed || !menuState) return;
       executeSlashCommand(editor.pm.view, menuState, item.action);
       editor.pm.view.focus();
     },

packages/react/src/components/TableHandles.tsx

@@ -36,9 +36,9 @@ import {
  */
 export interface TableHandlesProps {
   /**
-   * The OpenBlockEditor instance.
+   * The OpenBlockEditor instance (can be null during initialization).
    */
-  editor: OpenBlockEditor;
+  editor: OpenBlockEditor | null;
 
   /**
    * Additional class name for the handles container.
@@ -144,6 +144,8 @@ export function TableHandles({
 
   // Track mouse position to detect which row/col is hovered
   useEffect(() => {
+    if (!editor || editor.isDestroyed) return;
+
     let hideTimeout: ReturnType<typeof setTimeout> | null = null;
 
     const clearHideTimeout = () => {
@@ -286,7 +288,7 @@ export function TableHandles({
 
   const handleAddRow = useCallback(
     (index: number) => {
-      if (!tableState) return;
+      if (!editor || editor.isDestroyed || !tableState) return;
       addRowAtIndex(editor.pm.state, editor.pm.view.dispatch, tableState.tablePos, index);
       editor.pm.view.focus();
       setShowRowMenu(null);
@@ -296,7 +298,7 @@ export function TableHandles({
 
   const handleDeleteRow = useCallback(
     (index: number) => {
-      if (!tableState) return;
+      if (!editor || editor.isDestroyed || !tableState) return;
       deleteRowAtIndex(editor.pm.state, editor.pm.view.dispatch, tableState.tablePos, index);
       editor.pm.view.focus();
       setShowRowMenu(null);
@@ -306,7 +308,7 @@ export function TableHandles({
 
   const handleAddCol = useCallback(
     (index: number) => {
-      if (!tableState) return;
+      if (!editor || editor.isDestroyed || !tableState) return;
       addColumnAtIndex(editor.pm.state, editor.pm.view.dispatch, tableState.tablePos, index);
       editor.pm.view.focus();
       setShowColMenu(null);
@@ -316,15 +318,15 @@ export function TableHandles({
 
   const handleDeleteCol = useCallback(
     (index: number) => {
-      if (!tableState) return;
+      if (!editor || editor.isDestroyed || !tableState) return;
       deleteColumnAtIndex(editor.pm.state, editor.pm.view.dispatch, tableState.tablePos, index);
       editor.pm.view.focus();
       setShowColMenu(null);
     },
     [editor, tableState]
   );
 
-  if (!tableState) return null;
+  if (!editor || editor.isDestroyed || !tableState) return null;
 
   const tableRect = tableState.tableElement.getBoundingClientRect();
 

packages/react/src/components/TableMenu.tsx

@@ -39,9 +39,9 @@ import {
  */
 export interface TableMenuProps {
   /**
-   * The OpenBlockEditor instance.
+   * The OpenBlockEditor instance (can be null during initialization).
    */
-  editor: OpenBlockEditor;
+  editor: OpenBlockEditor | null;
 
   /**
    * Additional class name for the menu container.
@@ -207,6 +207,8 @@ export function TableMenu({
   const [coords, setCoords] = useState<{ left: number; top: number } | null>(null);
 
   useEffect(() => {
+    if (!editor || editor.isDestroyed) return;
+
     const updateState = () => {
       const state = editor.pm.state;
       const isInsideTable = isInTable(state);
@@ -247,41 +249,48 @@ export function TableMenu({
   }, [editor]);
 
   const handleAddRowBefore = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     addRowBefore(editor.pm.state, editor.pm.view.dispatch);
     editor.pm.view.focus();
   }, [editor]);
 
   const handleAddRowAfter = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     addRowAfter(editor.pm.state, editor.pm.view.dispatch);
     editor.pm.view.focus();
   }, [editor]);
 
   const handleDeleteRow = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     deleteRow(editor.pm.state, editor.pm.view.dispatch);
     editor.pm.view.focus();
   }, [editor]);
 
   const handleAddColumnBefore = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     addColumnBefore(editor.pm.state, editor.pm.view.dispatch);
     editor.pm.view.focus();
   }, [editor]);
 
   const handleAddColumnAfter = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     addColumnAfter(editor.pm.state, editor.pm.view.dispatch);
     editor.pm.view.focus();
   }, [editor]);
 
   const handleDeleteColumn = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     deleteColumn(editor.pm.state, editor.pm.view.dispatch);
     editor.pm.view.focus();
   }, [editor]);
 
   const handleDeleteTable = useCallback(() => {
+    if (!editor || editor.isDestroyed) return;
     deleteTable(editor.pm.state, editor.pm.view.dispatch);
     editor.pm.view.focus();
   }, [editor]);
 
-  if (!inTable || !coords) {
+  if (!editor || editor.isDestroyed || !inTable || !coords) {
     return null;
   }
 

packages/react/src/hooks/useOpenBlock.ts

@@ -19,7 +19,7 @@
  * ```
  */
 
-import { useEffect, useState } from 'react';
+import { useEffect, useRef, useState } from 'react';
 import { OpenBlockEditor, EditorConfig, Block } from '@labbs/openblock-core';
 
 /**
@@ -31,21 +31,25 @@ export interface UseOpenBlockOptions extends Omit<EditorConfig, 'element'> {}
  * Create and manage an OpenBlockEditor instance
  *
  * @param options - Editor configuration options
- * @returns The OpenBlockEditor instance
+ * @returns The OpenBlockEditor instance, or null during initialization
+ *
+ * @remarks
+ * This hook properly handles React 18+ StrictMode, which mounts components twice
+ * in development. The editor is created in useEffect to ensure a fresh instance
+ * is created after each mount/unmount cycle.
  */
-export function useOpenBlock(options: UseOpenBlockOptions = {}): OpenBlockEditor {
-  // Use useState with lazy initializer to create the editor exactly once
-  // This is React 18+ safe and works with StrictMode
-  const [editor] = useState(() => new OpenBlockEditor(options));
+export function useOpenBlock(options: UseOpenBlockOptions = {}): OpenBlockEditor | null {
+  const [editor, setEditor] = useState<OpenBlockEditor | null>(null);
+  const optionsRef = useRef(options);
 
-  // Cleanup on unmount only
   useEffect(() => {
+    const newEditor = new OpenBlockEditor(optionsRef.current);
+    setEditor(newEditor);
+
     return () => {
-      if (!editor.isDestroyed) {
-        editor.destroy();
-      }
+      newEditor.destroy();
     };
-  }, [editor]);
+  }, []);
 
   return editor;
 }