Rated 5 out of 5 stars
The addon is good, but the following functions are missing:
1. The scrollbar settings are missing. I know there is the NewScrollbars extension and I know that and the option to let it become useless.
2. Add icons to each (or most popular) Linux graphical environment (GNOME, KDE, LXDE and XFCE).
3. Add icons of the old and current versions of the Opera browser.
That's all for now.
1. This is a toolbar button add-on, not a button add-on in general. Scrollbar buttons, window buttons, popup/panel buttons are not affected on purpose.
2. There is one Linux icon set available in CTB from old Ubuntu versions, that I got with permission from the creator of Tangofox. Most Linux icons where automatically taken from OS files by Firefox before Firefox 29. There are not part of any old Firefox Linux setup/package.
3. I don't have those icon sets and one can not simply extract them from Operas installation files.