Hey, (especially @MikeT)
I mentioned this earlier in the release notes of 7.3 Beta 2
But now I finally got it captured (was not visible with a low framerate):
It only occurs, if it has to load the complete 240 items.
When I set a filter, lock and unlock there is no lag.
Maybe this gif helps, you said you would have an eye on it, thank you for that.
This is just for the record
1Password Version: 7.3.648
Extension Version: 18.104.22.168
OS Version: Windows 10 1809 17763.195
Sync Type: Dropbox