fix: ignore autoplay attribute mutations regardless of tagName case

.changeset/fix-ignore-attribute-tagname-case.md

@@ -0,0 +1,6 @@
+---
+"rrweb-snapshot": patch
+"rrweb": patch
+---
+
+Lowercase the tag name in `ignoreAttribute` so `autoplay` mutations on `<video>`/`<audio>` are ignored on the attribute-mutation path, which passes the native uppercase `target.tagName`

packages/rrweb-snapshot/src/snapshot.ts

@@ -209,7 +209,9 @@ export function ignoreAttribute(
   // eslint-disable-next-line @typescript-eslint/no-unused-vars
   _value: unknown,
 ): boolean {
-  return ['video', 'audio'].includes(tagName) && name === 'autoplay';
+  return (
+    ['video', 'audio'].includes(toLowerCase(tagName)) && name === 'autoplay'
+  );
 }
 
 export function _isBlockedElement(

packages/rrweb-snapshot/test/snapshot.test.ts

@@ -6,6 +6,7 @@ import { describe, expect, it } from 'vitest';
 
 import snapshot, {
   _isBlockedElement,
+  ignoreAttribute,
   serializeNodeWithId,
 } from '../src/snapshot';
 import { elementNode, serializedNodeWithId } from '../src/types';
@@ -159,6 +160,24 @@ describe('isBlockedElement()', () => {
   });
 });
 
+describe('ignoreAttribute()', () => {
+  it('ignores autoplay on lowercase media tag names', () => {
+    expect(ignoreAttribute('video', 'autoplay', '')).toEqual(true);
+    expect(ignoreAttribute('audio', 'autoplay', '')).toEqual(true);
+  });
+
+  it('ignores autoplay on native uppercase media tag names', () => {
+    expect(ignoreAttribute('VIDEO', 'autoplay', '')).toEqual(true);
+    expect(ignoreAttribute('AUDIO', 'autoplay', '')).toEqual(true);
+  });
+
+  it('does not ignore other attributes or other elements', () => {
+    expect(ignoreAttribute('video', 'src', '')).toEqual(false);
+    expect(ignoreAttribute('DIV', 'autoplay', '')).toEqual(false);
+    expect(ignoreAttribute('div', 'autoplay', '')).toEqual(false);
+  });
+});
+
 describe('style elements', () => {
   const render = (html: string): HTMLStyleElement => {
     document.write(html);