diff --git a/packages/lexical-react/src/LexicalExtensionEditorComposer.tsx b/packages/lexical-react/src/LexicalExtensionEditorComposer.tsx
index e5fb088d669..de03c04290c 100644
--- a/packages/lexical-react/src/LexicalExtensionEditorComposer.tsx
+++ b/packages/lexical-react/src/LexicalExtensionEditorComposer.tsx
@@ -8,11 +8,16 @@
 import {getExtensionDependencyFromEditor} from '@lexical/extension';
 import {ReactExtension} from '@lexical/react/ReactExtension';
 import {LexicalEditorWithDispose} from 'lexical';
-import {useEffect} from 'react';
 
 export interface LexicalExtensionEditorComposerProps {
   /**
-   * Your root extension, typically defined with {@link defineExtension}
+   * Your root extension, typically defined with {@link defineExtension}.
+   * The lifecycle of this editor is not owned by this component,
+   * you are responsible for calling `initialEditor.dispose()` if needed.
+   * Note also that any LexicalEditor can only be rendered to one root
+   * element, so if you try and use it from multiple components
+   * simultaneously then it will only be managed correctly by the last one
+   * to render.
    */
   initialEditor: LexicalEditorWithDispose;
   /**
@@ -33,18 +38,6 @@ export function LexicalExtensionEditorComposer({
   initialEditor: editor,
   children,
 }: LexicalExtensionEditorComposerProps) {
-  useEffect(() => {
-    // Strict mode workaround
-    let didMount = false;
-    queueMicrotask(() => {
-      didMount = true;
-    });
-    return () => {
-      if (didMount) {
-        editor.dispose();
-      }
-    };
-  }, [editor]);
   const {Component} = getExtensionDependencyFromEditor(
     editor,
     ReactExtension,
diff --git a/packages/lexical-react/src/__tests__/unit/LexicalExtensionEditorComposer.test.tsx b/packages/lexical-react/src/__tests__/unit/LexicalExtensionEditorComposer.test.tsx
index 753b62e5623..1f26115b92c 100644
--- a/packages/lexical-react/src/__tests__/unit/LexicalExtensionEditorComposer.test.tsx
+++ b/packages/lexical-react/src/__tests__/unit/LexicalExtensionEditorComposer.test.tsx
@@ -14,6 +14,7 @@ import {LexicalExtensionComposer} from '@lexical/react/LexicalExtensionComposer'
 import {LexicalExtensionEditorComposer} from '@lexical/react/LexicalExtensionEditorComposer';
 import {RichTextPlugin} from '@lexical/react/LexicalRichTextPlugin';
 import {ReactExtension} from '@lexical/react/ReactExtension';
+import {ReactPluginHostExtension} from '@lexical/react/ReactPluginHostExtension';
 import {ReactProviderExtension} from '@lexical/react/ReactProviderExtension';
 import {toHaveNoViolations} from 'jest-axe';
 import {
@@ -25,10 +26,13 @@ import {
   $getState,
   $getStateChange,
   $setState,
+  COMMAND_PRIORITY_EDITOR,
+  createCommand,
   createState,
   DecoratorNode,
   defineExtension,
   EditorConfig,
+  LexicalCommand,
   LexicalEditor,
   LexicalEditorWithDispose,
   StateConfigValue,
@@ -192,4 +196,93 @@ describe('LexicalExtensionEditorComposer', () => {
       await Promise.resolve();
     });
   });
+
+  test('does not dispose the editor on unmount', async () => {
+    using editor = buildEditorFromExtensions({
+      dependencies: [ReactPluginHostExtension, RichTextPlugin],
+      name: '[root]',
+    });
+    const TestCommand: LexicalCommand<number> = createCommand('TestCommand');
+    const handled: number[] = [];
+    editor.registerCommand(
+      TestCommand,
+      (payload) => {
+        handled.push(payload);
+        return true;
+      },
+      COMMAND_PRIORITY_EDITOR,
+    );
+
+    await ReactTestUtils.act(async () => {
+      reactRoot.render(
+        <LexicalExtensionEditorComposer initialEditor={editor} />,
+      );
+    });
+    expect(editor.getRootElement()).not.toBe(null);
+    expect(editor.dispatchCommand(TestCommand, 1)).toBe(true);
+    expect(handled).toEqual([1]);
+
+    await ReactTestUtils.act(async () => {
+      reactRoot.render(null);
+      await Promise.resolve();
+    });
+
+    // The command registration must survive the composer unmount —
+    // LexicalExtensionEditorComposer no longer calls editor.dispose().
+    expect(editor.dispatchCommand(TestCommand, 2)).toBe(true);
+    expect(handled).toEqual([1, 2]);
+  });
+
+  test('can remount with the same editor after unmount', async () => {
+    using editor = buildEditorFromExtensions({
+      dependencies: [ReactPluginHostExtension, RichTextPlugin],
+      name: '[root]',
+    });
+    editor.update(
+      () =>
+        $getRoot()
+          .clear()
+          .append($createParagraphNode().append($createTextNode('nested'))),
+      {discrete: true},
+    );
+
+    // First mount
+    await ReactTestUtils.act(async () => {
+      reactRoot.render(
+        <LexicalExtensionEditorComposer initialEditor={editor} />,
+      );
+    });
+    expect(container?.textContent).toBe('nested');
+    const firstRoot = editor.getRootElement();
+    expect(firstRoot).not.toBe(null);
+
+    // Unmount
+    await ReactTestUtils.act(async () => {
+      reactRoot.render(null);
+      await Promise.resolve();
+    });
+
+    // Remount with the same editor instance — this mirrors the image-caption
+    // open/close/open cycle that previously broke because the editor was
+    // disposed on first unmount.
+    await ReactTestUtils.act(async () => {
+      reactRoot.render(
+        <LexicalExtensionEditorComposer initialEditor={editor} />,
+      );
+    });
+    expect(container?.textContent).toBe('nested');
+    expect(editor.getRootElement()).not.toBe(null);
+
+    // Editor still functions for updates after the remount.
+    await ReactTestUtils.act(async () => {
+      editor.update(
+        () =>
+          $getRoot()
+            .clear()
+            .append($createParagraphNode().append($createTextNode('updated'))),
+        {discrete: true},
+      );
+    });
+    expect(container?.textContent).toBe('updated');
+  });
 });
diff --git a/packages/lexical-react/src/__tests__/unit/useExtensionSignalValue.test.tsx b/packages/lexical-react/src/__tests__/unit/useExtensionSignalValue.test.tsx
index d703dc6fbe7..78cd98c4606 100644
--- a/packages/lexical-react/src/__tests__/unit/useExtensionSignalValue.test.tsx
+++ b/packages/lexical-react/src/__tests__/unit/useExtensionSignalValue.test.tsx
@@ -192,7 +192,7 @@ describe('useExtensionSignalValue', () => {
       name: 'test',
     });
 
-    const editor = buildEditorFromExtensions({
+    using editor = buildEditorFromExtensions({
       dependencies: [ReactPluginHostExtension, TestExtension],
       name: '[root]',
     });
@@ -284,7 +284,7 @@ describe('useExtensionSignalValue', () => {
       name: 'test',
     });
 
-    const editor = buildEditorFromExtensions({
+    using editor = buildEditorFromExtensions({
       dependencies: [ReactPluginHostExtension, TestExtension],
       name: '[root]',
     });
@@ -337,7 +337,7 @@ describe('useExtensionSignalValue', () => {
       name: 'test',
     });
 
-    const editor = buildEditorFromExtensions({
+    using editor = buildEditorFromExtensions({
       dependencies: [ReactPluginHostExtension, TestExtension],
       name: '[root]',
     });
@@ -380,7 +380,7 @@ describe('useExtensionSignalValue', () => {
       name: 'test',
     });
 
-    const editor = buildEditorFromExtensions({
+    using editor = buildEditorFromExtensions({
       dependencies: [ReactPluginHostExtension, TestExtension],
       name: '[root]',
     });