CKeditor5 source code editor breaks with a <template> tag

Is there an issue report at https://github.com/ckeditor/ckeditor5/issues?

Yes: https://github.com/ckeditor/ckeditor5/issues/14933. It would have been good to provide that link.

The issue is not appearing when using gin admin theme → for admin.

Closed 🐛 Ckeditor not allowing Closed: duplicate as a duplicate bug report. Crediting @ravi kant 👍

What will be solution if not using <a href="https://www.drupal.org/project/gin">gen admin theme</a>?

It seems https://github.com/ckeditor/ckeditor5/issues/14933 is fixed in ckeditor5 and hope will be included in next release.
Can we make this issue active?

We just updated Drupal core to CKEditor 5 40.1.0 in 📌 Update CKEditor 5 to 40.1.0 Fixed . So it will be quite some time until this will be available to us. So still kinda blocked on upstream …

But, we are able to test this using 🌱 [meta] Test against CKEditor 5 nightly Active ahead of an upstream release 😃

Let's begin with writing the necessary test coverage? 🙏

https://github.com/ckeditor/ckeditor5/issues/14933 was fixed upstream.

This will ship in CKEditor 5 40.2.0 per https://github.com/ckeditor/ckeditor5/issues/14724.

Monitor 📌 Update CKEditor 5 to 40.2.0 RTBC .

Can somebody who has run into this please check out the MR at 📌 Update CKEditor 5 to 40.2.0 RTBC , or apply its patch, and verify that this has been fixed? 🙏

📌 Update CKEditor 5 to 40.2.0 RTBC landed, so now you can just test 10.2.x, or soon: 10.2.0! 😊

Not sure the right status,

But tested on my 11.x install with Standard profile.
Followed the steps in the issue summary
Did not see any console errors or anything in the logs.

Is that what you were looking for @Wim leers?

I'm triaging RTBC issues → . I read the IS and the comments.

There is a question in #16 for @Wim Leers. That should be resolved before this is set to RTBC.

Wonder if this is the right status

Per #16, the bug was fixed upstream, the only thing we still need here is explicit test coverage in SourceEditingTest.

#18: No it wasn't 😅

Hi all! I’ve taken a first pass at a FunctionalJavascript test for this issue and I’m running into two blockers:

With filter_html enabled (and <template> added to the allowed tags), the <template>element is still stripped from the editor.

If I disable filter_html, the <template> tag itself remains, but its inner content is stripped when saved/rendered.

I’ve pushed my current code to the MR and would appreciate any suggestions or feedback to help me move this forward. Thank you!

1 the issue summary is incomplete.

MR just contains a test without a fix so not sure what to review here.