Repository navigation
YouTube embed previews fail with Error 153 in Safari #73288
Description
Description
YouTube embed previews fail to load in the editor when using the Safari browser. Rather than displaying the YouTube video, a Error 153 Video player configuration error is displayed. This issue does not occur in Chrome.
Step-by-step reproduction instructions
- Create a new post.
- Insert the YouTube Embed block type.
- Paste a valid YouTube video URL.
- Click Embed.
Screenshots, screen recording, code snippet
youtube-embed-flow.mov
Environment info
- WordPress 6.8.3
- Gutenberg 22.0.0
- macOS 26.1
- Safari 26.1 (21622.2.11.11.9)
Please confirm that you have searched existing issues in the repo.
- Yes
Please confirm that you have tested with all plugins deactivated except Gutenberg.
- Yes
Please confirm which theme type you used for testing.
- Block
- Classic
- Hybrid (e.g. classic with theme.json)
- Not sure
Activity
dcalhoun commentedon Nov 14, 2025
My perception is this error relates to YouTube requiring a referrer for embeds. This requirement was documented on July 7, 2025, but YouTube may have begun enforcement more recently.
From my testing, it seems Gutenberg's usage of
iframes (and the attributes used) for the editor canvas and embeds play a role, nullifying theoriginorreferrerreported for the YouTube embed. I'm unsure of the best solution at this time.ellatrix commentedon Nov 17, 2025
I can only reproduce in Safari, both Chrome and Firefox work fine.
jkmassel commentedon Nov 17, 2025
This seems to be caused by https://bugs.webkit.org/show_bug.cgi?id=169846.
dcalhoun commentedon Nov 17, 2025
To build upon the seemingly relevant Safari issue, I'll note additional findings. It appears setting
srcto a blob URL also causes Safari to exclude theHTTP_REFERER.I explored modifying the approach for populating the
iframes in the editor, the outcome differed.srcwith a blob URLsrcwith a non-blob URL (e.g.,http://[...])srcDataiframecontentswestonruter commentedon Dec 10, 2025
Core-64395 was marked as a duplicate.
larskuhnt commentedon Mar 31, 2026
I think Safari orders the referrer policy in a different way than other browsers do. If your page has e.g.
<meta name="referrer" content="no-referrer" />the iframe attributereferrerpolicy="strict-origin-when-cross-origin"is ignored and the referrer is not sent in iframe requests. The page meta tag needs to define<meta name="referrer" content="strict-origin-when-cross-origin" />to allow referrer headers in iframe requests.