Review for ProfileSwitcher by Andrew Lee
Rated 5 out of 5 stars
Works great but would it be possible to actually preload the profile first to make it look almost seamless?
Maybe altering the one window mode then running it hidden until loaded then set it back.
Either way the add-on is great def worth trying if you change profiles a lot.
To create your own collections, you must have a Mozilla Add-ons account.