Another mock layout to consider:
K so hovering search shows both search bar and next to it a tag button that are essentially easy keywords to search for too.
You would edit the favorites from within Krita settings.
Favorites are shown by clicking the Normal (current active mode) button.
And also from Krita’s settings you would edit which modes appear in what tag you created. The current expandable categories would be pre-created tags out of the box that you can delete and restore.
You could also perhaps sort order of the tags and size of text. If large add a wide scroll down button/then up button along the bottom of the tag “div” container