Have you tried `firefox --no-remote --profile <path>`?

In my case, I am able to launch several Firefox instances with distinct profiles.

Note that `--no-remote` breaks starting new browser windows from outside, which users normally want.

I'm starting to think that setting the `HOME` environment variable is the only way to really make things isolated - this still won't handle `~insertusernamehere` but basically everything else respects it.

	▲	glandium 6 hours ago \| parent [-]
		--no-remote doesn't do anything anymore. It was removed about a year ago if memory serves.

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rc_kas 7 hours ago | parent | prev | next [-]

I do `open -n "/Applications/Firefox.app" --args -p myprofilename` and that does the trick on mac

	▲	UltraSane 4 hours ago \| parent [-]
		On windows powershell I do Start-Process "C:\Program Files\Mozilla Firefox\firefox.exe" -ArgumentList "-P default-release" Which is the exact same idea.

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bluebarbet 10 hours ago | parent | prev [-]

Yes, I tried that and everything else. Either it refuses to launch with `--new-instance` or (from memory, in the case of your command) subsequent `--new-tab`s may open in the wrong profile. Presumably due to the order in which the original instances were created. The point is that the system turns on these UIDs, which are not paths or even hashes of paths.