[5.x]: CKEditor fields in nested entry slideouts trigger unsaved changes immediately on open

[superflausch]

What happened?

Description

In some cases, CKEditor fields inside nested entry slideouts immediately trigger the unsaved changes state as soon as the slideout is opened, even though no changes were made.

This does not happen in every case, but it becomes reliably reproducible once the field contains certain “special” content elements. So far, I have confirmed the issue with:

• Bulleted List
• Nested Content

There may be other elements that cause the same behavior as well, but I have not tested all of them yet.

We are seeing this on an existing project, and I was also able to reproduce it on a clean Craft CMS install.

I’m not completely sure whether this belongs to the CKEditor field/plugin or to Craft CMS itself, but since it only seems to happen when the field is nested within another entry, I thought it made sense to report it here.

Steps to reproduce

1. Create a content model like this: Pages (Section) → Page (Entry Type) → Sections (Matrix field, "Cards" view mode) → Section (Entry Type) → Blocks (Matrix field, "Blocks" view mode) → Rich (Entry Type) → Rich (CKEditor field)
2. Configure the CKEditor field so it allows content such as: Bulleted List, Nested Content
3. Create a nested entry in the Sections field, then add a deeply nested entry to its Blocks field using the Rich entry type. In its Rich CKEditor field, add either a Bulleted List or Nested Content, then save the entry.
4. From the root owner entry, double-click the Section nested entry card to open its slideout.
5. As soon as the slideout opens, the unsaved changes behavior is triggered.

Expected behavior

Opening the slideout should not trigger the unsaved changes indicator, since no edits were made.

Actual behavior

The unsaved changes indicator is triggered immediately when the slideout opens, even though nothing was changed.

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Craft CMS version

5.9.18

PHP version

No response

Operating system and version

No response

Database type and version

No response

Image driver and version

No response

Installed plugins and versions

• CKEditor 5.3.1

[linear]

CMS-1929

PT-3085

[i-just]

Hi, thanks for reporting! I raised a PR for this.

[brandonkelly]

CKEditor 5.4.0 is out with the fix for this. Thanks again!