This is the shortcut I use to open the current browser to youtube;

"C:\Program Files\Mozilla Firefox_Current\firefox.exe" -p default-release YouTube.com

Note the -p switch to open a selected profile. Not needed if you only have one profile.

You can't set the default profile via the command line, if Firefox is set to remember the last used profile in the profile manager then this profile will be set automatically as 'Default=1' in profiles.ini. Otherwise you would have to parse profiles.ini and remove the 'Default=1' flag for the currently set profile and then set it to the wanted profile. See also:

• https://support.mozilla.org/en-US/kb/dedicated-profiles-firefox-installation

You can't set the default profile via the command line, if Firefox is set to remember the last used profile in the profile manager then this profile will be set automatically as 'Default=1' in profiles.ini. Otherwise you would have to parse profiles.ini and remove the 'Default=1' flag for the currently set profile and then set it to the wanted profile. See also:

• https://support.mozilla.org/en-US/kb/dedicated-profiles-firefox-installation

Well i guess i have to make this small batch script into a full blown python program :( Thanks for the reply btw.

I hope a flag like: `--set-default-profile` could be added in the future.