This is by far the thing I hate the most about @Firefox
If a background update is installed then you can't create any new tabs without restarting. This happens a lot.pic.twitter.com/6WWZwRW7UZ
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For the record I've NEVER seen this screen, didn't even know it existed. May be a Mac-only constraint with different process versions?
I don't use a Mac, I'm on Linux.
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