Auto Toggle Vertical Tab автор Reguna

Check the width of currently focused Firefox window periodically (every 0.1 second):

1. If width <= user defined threshold, enable vertical tab
2. If width > user defined threshold, disable vertical tab

The user defined threshold is 1080 (in pixels) by default.
You can edit this value in the extension popup menu.

This extension is open source (GPLv3) and does not collect any data nor send any data to any server.
https://github.com/regunakyle/firefox-auto-vertical-tab