libraries-override failed: ckeditor/drupal.ckeditor.plugins.drupalimagecaption

Problem/Motivation

My understanding of "libraries-override" that will override and only load the final target:
https://git.drupalcode.org/project/drupal/-/blob/9.2.x/core/themes/stabl...

But we could see the Drupal loaded both original and overrided

ckeditor.drupalimagecaption.css is loaded twice when using image captions in CKEditor.

Steps to reproduce

1. Turn on Stable9
2. Create a new Article
3. Add image
4. Save and check node/(node-ID)

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes

Release notes snippet