It is happening a lot lately since the last update... when I use the 1Password extension in either Firefox or Chrome it freezes and I have to kill it with Activity monitor using Force Kill.
Chrome: Version 60.0.3112.78 (Official Build) (64-bit) extension 220.127.116.11
Firefox: 54.0.1 (64-bit)
1Password: 6.8 (68005)
1Password Version: 6.8 (680015)
Extension Version: 18.104.22.168
OS Version: MacOS 10.12.6
Sync Type: Agilebits