Ctrl+Click or middle click on any link. Now press Ctrl-W. The tab does not close, another tab is opened for that link instead.
Lovely.
NOTE:
I use FF primarily, and Opera Dev (Oink). Prior to 2012 (1999-2012) I used Opera (versions 5-12) 99%+ of the time.
The FireFox "+ Customize" along with UserJS and UserCSS gives you most of the freedom that Opera users used to have with regards to control over the UI.
I know I'm thankful Firefox is still around, and I wouldn't of been caught dead using it back in Opera's heyday.
To me the biggest slap in the face in regards to "Chrome/Blink" --- you aren't even allowed to reorganize extension icons on the "address bar". You cannot/are not allowed to move extension icons to any other place in the interface. Chrome's UI is so locked down as to make a comparison between a blink-based browser and gecko-based browser almost impossible as far as the UI is concerned.
guaranteed memory safety threads without data races
Sounds like an excellent usage of engineering time. Reinvent the Wheel, make it square this time though!
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