Tabs bar

Space for tabs within the existing bar (not just in the Settings) is limited. If you have a lot of addons that add their frontend part, this bar space can be easily exhausted. Currently, it cuts, effectively hiding any overflowing tabs. Can be easily reproduced just by resizing window width.

We could collaps tabs to dropdown menu if real estate is missing, or just add it as the left-most item, or even wrap them on new line.