Allow to insert icons into editor-enabled textareas

[docwilmot]

Description of the need

It has been stated that "Adding the ability to use Icons in CKEditor for content, might be the single most userful use of an icon picker in core." @stpaultim 2026.

Proposed solution

Options to enable this include:

1. Modify the image library to also serve icons, dialog reuses the current image library button
2. Add a separate CKEditor button that launches the icon browser as a standalone dialog

Noting here that a separate dialog would likely duplicate functionality, since the dialog should ideally also offer image resizing, alt text, captioning, etc, already provided in the image library dialog.

Alternatives that have been considered

Do this all in contrib

Additional information

Some progress creating option 1 above.
https://github.com/user-attachments/assets/f457cdcb-f6cb-4adb-825b-e03bfc71ebec

Draft of feature description for Press Release (1 paragraph at most)

Backdrop now allows to insert icons in editor-enabled textareas through the image library

[argiepiano]

This would be great. We probably need to code a custom plugin for CKE. This plugin would also be SUPER helpful to insert tokens. Currently, the token browser is unable to automatically insert tokens into CKE text areas (the only way to do that is to manually copy/paste the token).

[docwilmot]

Firs try PR pushed up. AJAX Paging and filtering in the icon browser does not yet work!!