Excellent. I would suggest being able to resize the sidebar to the right some more (perhaps half screen).

Like other said, a list of the sites inside the sidebar or perhaps a menu like Opera does the sidebar.

Just ideas, great work!

Very simple and easy to customize for people who close to CSS

Support site down, so have to leave a request here: If a site has no icon, the title should still be lined up with the other titles, i.e. there should be an empty space of the same size as an icon. Please line up by default or suggest a custom CSS for that.

is it possible to add per-tab persistence configuration? that would be very useful esp. on pdfjs tabs (which is local, and might be restricted therefore)

Perfect, thanks

Amazingly useful and innovative.

We can create "marker tabs" at will, but we can rename one only when we create it, as follows:

(right click anywhere on the left side list of tabs)
> new marker tab
> (in the address bar, replace "MarkerNameHere" with the name of your choice. It also accepts spaces.)
> (type the ENTER key)

This addon is also open source and does not require any dangerous permissions.
I was using "tree style tab" before, but the multiple level of folding were very annoying to me.
Thanks a lot :)

Great combination of tab grouping and tab menu. Simple, helpful, and unobtrusive. Two things would make it really great: dim unloaded tabs and tab search or filtering. But I still give it 5 stars because I love the easiness and clever simplicity.

is it possible for me to submit a pull request? I added a feature. Please contact me: temp954335@czxzyyyk.de

Simple,useful,efficient extension deserving 5Stars.

It's simple but does what it's supposed to. No complaints.

I have tried all the Vertical Tabs extensions post-FF59 I could find, and this is definitely the best!
Simple, fast, does not mess with the opening and closing ordering of tabs and focus change, allows drag & drop of tabs between windows.

The speed gain on all FF tab operations compared to others extensions such as "Power Tabs" is really noticeable.

The only missing feature is a way to "detach" a tab into a new window (I have to use the tab on the top of the window, or create a new window and drag+drop the tag there), unless I have missed something.

Tab Sidebarシンプルであること、それがとても良いです。
Default Style Sheetを見ることができるのもうれしい。
サイドバーに表示されたタブをマウスホイールで切り替えることもオプションで可能となりました。
ありがとうございます。

Exactly what I was looking for.