Switchable sorting function

[zen0bit]

Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is. Ex. I'm always frustrated when my panel traveling.

I usually have a lot of tabs. If i open link to site bounded to container this tabs travel alllll the way to right place, it can get up to minute..

Describe the solution you'd like
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Switchable sorting functions, so tabs can open as in base firefox and not go to own group

[metastable-void]

Also, the tab sorting function is I think not fully optimized, so it could be faster.

I will add a preference to turn off tab sorting.

[metastable-void]

Updated to use the state-of-the-art sorting algorithm. 1867e71

[metastable-void]

This should be faster up to 100x, when we have hundreds of tabs.

[metastable-void]

For perfection, I just added an option to disable sorting of tabs (5bd10f6).

[metastable-void]

This feature is included in the next 11.6.0 release.
#183