Front-End-Checklist 是做什麼的?
Use when applies to all <video> elements and third-party video embeds (YouTube, Vimeo) where the page owner controls the content. Prerecorded videos require .vtt caption files via <track>. For videos embedded via <iframe>, check that the video platform captions are enabled. Audio-only content requires transcripts instead (SC 1.2.1). Video-only content (no audio) requires a text alternative or audio description instead (SC 1.2.3).