Images should be pasteable via clipboard ctrl+V as a shortcut, similar to how Github's MD editor works. This would be a gigantic time saver.

Writing tables in markdown is very difficult and annoying. It would be nice if you could add this ( https://github.com/susisu/mte-kernel ) or similar package to handle them. This looks easy to implement, and could improve markdown a lot. A little effort will bring many benefits.

Looking for a nice way to create a complete wiki backup which contains Users, Settings and Content. And a way to import it in the setup wizard after Installing the wiki

Both mermaid and Draw.io integrations are phenomenal. Just thought that it is unfortunate that they don't end up using the entire real-estate.

Currently when moving or renaming a page, all existing links point to the old page. The correct behaviour would be to update all links to the new page, either optional or explicit.

Ability to delete folders in the Image / File Manager.

Give the option to change favicon via administration

Have a template or transclusion function, just like in MediaWiki( https://www.mediawiki.org/wiki/Help:Templates ), which would give people the ability to create infoboxes or other types of templates that are used on many other wikis.

Looking for a nice way to share (formatted) wiki pages with external links intact

Save current state of the buffer when editing a page, so in case the page is closed or the browser crashes, the work is not lost. This would work better with a warning when the page has been changed since the time the draft was saved.