CKEditor 5 not working on custom block creation/editing if both Admin Toolbar Search and JS aggregation are activated

I was just about to report a similar issue. With Admin Toolbar Search active it is impossible to change Text Edidor settings in Blocks. All is fine in Content type.

D10, PHP8.1, CKEditor 5

Hi, I have similar issue. But in my case it is only caused by JS aggregation. I have admin toolbar search permanently uninstalled. If I turn on JS aggregation CKEditor 5 not working at custom block edit page.

Adding a comment regarding taxonomy_term forms, where JS breaks if the description field is enabled (and has ckeditor-enabled text formats available to it). For me it did not matter whether aggregation was on. But uninstalling admin_toolbar_search makes the errors disappear.

Can reproduce this issue. Tried admin_toolbar 3.3.0 and also 3.2.1, both have the same issue. When javascript aggegation is enabled, ckeditor will not be loaded on /block/add. Also dropdown menu's in toolbar are not working.

Adding /block/add/* @ /admin/config/development/performance to prevent minification on those pages does not solve this issue.

Errors in console:

Uncaught TypeError: t.widget is not a function
Uncaught TypeError: Cannot set properties of undefined (setting 'ckeditor5')
Uncaught TypeError: Cannot read properties of undefined (reading 'prototype')
Uncaught TypeError: Drupal.toolbar.ToolbarModel is not a constructor

Same problem. As soon as js aggregation is turned off the editor appears in the block edit form. If aggregation is on = no editor.