To the people complaining about shrinked search results or that unmatched tabs not hide... you should take a look at the setting where you can change exactly those behavior. Even a look at the Screenshots would have lead you to that conclusion.
You decided to give a bad review instead...

A life saver in tabbed Internet. I have been waiting for a search feature in Tree Style Tabs since years, until I found out that TST offers nice extensions and has a capable API.

Currently doesn't support using the extension's toolbar button while having the browser's toolbar, where the extension's button is, at the bottom of the browser. Extension's window opens below the button, putting the window out of view. Not really a huge deal as it is integrated into TST, so it is still useable.

Working great for me. This also works across containers which not even the native FF tab search does.

It does what it says, and it does it well

Excellent! Really helps me organize my ridiculous collection of tabs.

Good!
Add dark theme accounting to the settings page. Now I have to write the userCintent style myself.
And the possibility of translation is desirable.

Love the addon. It would be cool to have a setting that searches based on tab content but that would probably be pretty extra.

Not many reactions to messages, but the extension works. Great job.