Go to https://addons.mozilla.org/en-US/firefox/addon/1password-x-password-manager/?src=search and you will see that the version offered there is 1.12.3 - and was last updated Nov 12, 2018. I just downloaded the Firefox extension from 1Password and got version 18.104.22.168. The two versions really are different. The one from the Firefox add-on page barely works.
I apologize for the duplication if this is a known problem, but none of my searches turned up anything like this in this forum.
1Password Version: 7.1.2 (70102000)
Extension Version: 1.12.3, 22.214.171.124
OS Version: OS X 10.13.6
Sync Type: 1Password account
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