Feature: #99678 - Improved link handling in the rich text editor 

Description 

The link plugin of the CKEditor 5 based rich text editor now resolves TYPO3 specific link targets such as t3://page?uid=3 to human readable information and uses it in the places where editors interact with links.

• Inserting links: When a link is inserted without selected text, the link title (if filled) or the title of the link target, for example the page title, is used as link text instead of the raw link. The inserted link stays selected afterwards, so it can be adjusted right away.
• Link preview: The balloon shown for a link now displays the icon, the title and the path of the target instead of the raw link. An additional button opens the link in a new tab.
• Opening links: Ctrl + click (Cmd + click on macOS) and Alt + Enter open the resolved frontend URL, or the public URL of a file, instead of the unresolvable t3:// link.

The information is provided by the new backend AJAX route link_preview, which respects the page permissions of the current backend user.

Impact 

Editors get a link workflow comparable to other modern editors. The generated HTML output of links is unchanged.