Cannot insert an image in WYSIWYG mode with the new image dialog after upgrading XWiki

Steps to reproduce:

• Take a clean XWiki 13.10.5 (or any older version that ships with CKEditor Integration 1.61 or below, which doesn't have the new image dialog)
• Open Wiki Administration > Editing > WYSIWYG Editor and check the list of "Disabled Plugins": the 'xwiki-image' plugin is not disabled (you can search for it when opening the drop down); moreover, there's no 'xwiki-image-old' plugin
• Save the configuration (no need to change anything, but the result is the same if you change)
• Open the Extension Manager administration section, search for the CKEditor Integration extension and upgrade it to version 1.62 (or any newer version); 1.62 is the version when the new image dialog was introduced, see CKEDITOR-436
  • Alternatively, you can get the same result by upgrading XWiki to 14.3-rc-1+ / 13.10.6+, i.e. any version that has CKEditor Integration 1.62+ (see XWIKI-19643)
• Clear the browser cache
• Go back to Wiki Administration > Editing > WYSIWYG Editor and check again the list of "Disabled Plugins"; the 'xwiki-image' plugin is still not disabled, but if you search for 'xwiki-image' in the drop down you'll now see both 'xwiki-image' and 'xwiki-image-old'; this means the new image dialog is enabled
• Edit a wiki page with the WYSIWYG editor to see that the new image dialog is enabled (even though it's experimental)
  • From CKEditor's toolbar, click Image
  • Select an image from the Document Tree or Upload an image
  • Click Select > Insert => the image is not inserted and there is a JavaScript error in the console
• If you go back to Wiki Administration > Editing > WYSIWYG Editor and disable the 'xwiki-image' plugin (and save) then you get the old (working) image dialog

In browser's JS console, there are the following errors:
 

Uncaught (in promise) TypeError: Cannot read properties of undefined (reading 'selectize')
    at n (imageWizard.bundle.min.js:12:427)
    at imageWizard.bundle.min.js:8:281

Uncaught TypeError: Cannot read properties of null (reading 'insertBefore')
    at window.CKEDITOR.window.CKEDITOR.dom.CKEDITOR.dom.element.insertBefore (ckeditor.js:71:324)
    at window.CKEDITOR.window.CKEDITOR.dom.CKEDITOR.dom.element.replace (ckeditor.js:79:123)
    at Object.d [as inflate] (ckeditor.js:1167:299)
    at h.shiftState (ckeditor.js:1192:179)
    at h.data (ckeditor.js:1169:412)
    at b.data (ckeditor.js:1484:367)
    at b.data (ckeditor.js:1484:367)
    at e.data (ckeditor.js:1492:283)
    at h.l (ckeditor.js:10:246)
    at h.fire (ckeditor.js:12:91)

This issue was reproduced also in XWiki 13.10.8, but not reproduced in XWiki 14.6 or 14.4.2.