Great extension! I love being able to organize my tabs in this way, have been using this for a few years now.

Minor complaint:
The recent update that recently (I think?) introduced keyboard shortcuts that interfere with nominal text editing, e.g. Ctrl + Shift + Left/Right, which I use for highlighting words.
The keyboard shortcut editor is generally buggy, as I can't figure out how to disable a key; trying to set it to something useless, like Ctrl + Shift + / or pressing ESC, doesn't work; I can only sometimes set it to "undefined".

May just jump directly to wherever the config lives and kill the keys.

EDIT: Hup, it's already filed and fixed - awesome!
https://github.com/piroor/treestyletab/issues/1995