Sen - For Tree Style Tabs от Sen

- Tree Style Tabs
https://addons.mozilla.org/en-US/firefox/addon/tree-style-tab/
- Further customization for TST
https://drive.google.com/drive/folders/12xgzyWC2Ko1JjZbgIaFBo14bh3uE_Ab7?usp=drive_link
Including:
+ Rounded corner
+ Margin
+ No Header
+ Auto-hide
For treestyletab.css, go to
Manage extention > TTS > Option > Appearance > Proton > Advanced > go to bottom > Load from File