My only complaint about arch/i3 so far is that updating Firefox forces a restart of Firefox, and I've got FF windows scattered over a few workspaces so I need to sift them back to their places.
Come to think of it I can probably prune one of the windows...
Would it be possible to create a script to save the desktop and screen position for each firefox window on close and restore them to the recorded desktops and positions on open? I haven't used i3 much (or arch at all), but I'm fairly certain I did something similar using Xubuntu some years back.
I'm vaguely aware of tools that'll do it for i3 but thus far I've just avoided restarting as much as I can. The call-out to James Mickens is not altogether inaccurate (:
Keep in mind that you can downgrade firefox back after the update with pacman -U /var/lib/something, then just refresh/keep using the open windows with no issue.
Come to think of it I can probably prune one of the windows...
ETA: and maybe one of the workspaces...