[euid]

Alternatively: I was thrown off by the new tab behavior in Tree-Style Tabs and didn't want the complexity of a tree of tabs. Vertical Tabs Reloaded[0] gives me the "tabs in a sidebar to the left" without the complexity.

[0]: https://addons.mozilla.org/en-US/firefox/addon/vertical-tabs...

[oarabbus_]

How does this help? Easier to read tab titles since it's horizontal?

[square_usual]

You can fit more tabs while still being able to read them, basically.