I've always used the -ProfileManager command line option in the past and shortcuts to "-P <profilename>" when wanting to launch/send actions to sessions. (didn'

I've always used the -ProfileManager command line option in the past and shortcuts to "-P <profilename>" when wanting to launch/send actions to sessions. (didn't know of about:profiles UI, neat) I haven't played with MAC (Multi-account Containers) yet but I understand they're a lightweight version of Profiles that can co-exist in a single browser session and have a bunch of neat features (like auto-binding certain sites to certain containers when visited). Would recommend trying out if you've been dissatisfied with the previous approach.