Didn't know you could do this with Firefox. Thanks for the tip! Curious — have you ever heard of Shift (tryshift.com)? It pretty much does the same thing, but with everything (Gmail, Facebook, YouTube, WhatsApp, etc.). I use it at work so that I don't have to sign in and out of all my Google accounts. It's pretty unreal.
Welcome to HN. Is this you?[1] You should disclose your job is promoting the company you mentioned if it is. I hope it isn't or you just forgot. Astroturfing erodes trust between people and makes the world worse.
