Editor and Filter won't work after Updating to D11

Problem/Motivation

After Upgrading from Drupal 10.5 to 11.2.0, we faced following two issues:
1. The CKEditor with active Cookie Content Blocker button does not appear on the content edit form, and following JS error is logged in the browser console:

TypeError: e.icons is undefined
    d https://www.example.com/modules/contrib/cookie_content_blocker/js/build/cookieContentBlocker.js?sypqcf:1
    _createForm https://www.example.com/modules/contrib/cookie_content_blocker/js/build/cookieContentBlocker.js?sypqcf:1
    init https://www.example.com/modules/contrib/cookie_content_blocker/js/build/cookieContentBlocker.js?sypqcf:1
    promise callback*./packages/ckeditor5-core/src/index.ts/init/m/< https://www.example.com/core/assets/vendor/ckeditor5/ckeditor5-dll/ckeditor5-dll.js?v=45.2.0:5
    m https://www.example.com/core/assets/vendor/ckeditor5/ckeditor5-dll/ckeditor5-dll.js?v=45.2.0:5
    init https://www.example.com/core/assets/vendor/ckeditor5/ckeditor5-dll/ckeditor5-dll.js?v=45.2.0:5
    initPlugins https://www.example.com/core/assets/vendor/ckeditor5/ckeditor5-dll/ckeditor5-dll.js?v=45.2.0:5
    create https://www.example.com/core/assets/vendor/ckeditor5/editor-classic/editor-classic.js?v=45.2.0:4
    create https://www.example.com/core/assets/vendor/ckeditor5/editor-classic/editor-classic.js?v=45.2.0:4
    attach https://www.example.com/core/modules/ckeditor5/js/ckeditor5.js?sypqcf:373
    editorAttach https://www.example.com/core/modules/editor/js/editor.js?v=11.2.0:304
    attach https://www.example.com/core/modules/editor/js/editor.js?v=11.2.0:228
    attach https://www.example.com/core/modules/editor/js/editor.js?v=11.2.0:211
    attachBehaviors https://www.example.com/core/misc/drupal.js?v=11.2.0:166
    attachBehaviors https://www.example.com/core/misc/drupal.js?v=11.2.0:162
    <anonymous> https://www.example.com/core/misc/drupal.init.js?v=11.2.0:32
    listener https://www.example.com/core/misc/drupal.init.js?v=11.2.0:20
    domReady https://www.example.com/core/misc/drupal.init.js?v=11.2.0:26
    <anonymous> https://www.example.com/core/misc/drupal.init.js?v=11.2.0:31
    <anonymous> https://www.example.com/core/misc/drupal.init.js?v=11.2.0:34
ckeditor5.js:467:19

2. For existing content where media was inserted via the cookie content blocker before the upgrade, you can no longer unblock the media content in the frontend with ‘Show content’ - nothing happens when you click on it.