nice and simple

Excellent! It should be FF by default :-) Gives more space verticaly on your computer screen. One can see tab names regardless of number of tabs which makes reviewing and switching between tabs quicker and easier.

Just what i was looking for!

Thanks, it is lovely (and most practical of course) !! ;)

best

Поставил после того как услышал от @bobuk в подкасте Radio-T, классное расширение, именно то что мне нужно, особенно радует иерархия

Superb. I'm hugely impressed by amount of features, details and configuration options in this extension. Used Tree Style Tab for months and now Sidebery is my extension of choice.

There is only one (but quite big) issue with usage of this extension, but it's not really fault of the author. Lack of customizable keyboard shortcuts, especially being able to bind switching to next/previous tab to something like CtrL+Q/Ctrl+E. That's an absolute shame for Firefox that it doesn't allow that.