[aapjesverkoper]

Thanks, this seems to work. I found the no-remote option when looking around, but accidentally lauching private_dot_com (nsfw) a couple of times at work instead of my private profile ended my testing with this last time.

[myfonj]

Yup,

    c:\apps\firefox\firefox.exe -no-remote -profile "C:\profiles\some-clean-profile"

was my was-to-go method for testing various configurations.

Knowing about

    %USERPROFILE%\AppData\Roaming\Mozilla\Firefox\profiles.ini

is also often helpful, eg. when you want to move certain profile folder.