Since tab groups were removed from Firefox, I've used windows as a replacement for groups*.
Which has taught me one thing:
The Firefox "cmd+`" window order algorithm might as well be a 

roll.
(* I've tried all the tab group extensions... different story for another day.)
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"keeping you on your toes heuristics"
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Rage Against the Design.
End of conversation
New conversation -
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I remembered one option where the values are numeric... But maybe it changed. With this ctrl+tab and other changes go in a logical order (at least for me)pic.twitter.com/88MobtXVkQ
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browser.ctrlTab.recentlyUsedOrder to false
End of conversation
New conversation -
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