Videos do not play in the lightbox

Symptom

A video item opens a blank slide, or a link instead of a player.

Cause

• The service behind the link is not supported. The free plugin plays YouTube and Vimeo links.
• The video is private, or embedding is turned off on it.
• A self-hosted file is in a format the browser cannot play.

Fix

1. Check the service against the list on Project Formats.
2. Allow embedding on the video, and make it public.
3. Use MP4 (H.264) for self-hosted files.

YouTube’s Sign in to confirm you’re not a bot prompt on background videos was addressed in 3.8.0, so update the plugin if you see it.