Occasionally, the key hole icon in Firefox 55.0.3 with extension 188.8.131.52 installed is disabled so that I cannot view the 1P menu to find the login I want. I have not found a consistent set of circumstances that cause this. It seems to happen when I may close a tab on a login page when I have tried to find the web site in 1P using the key hole icon in Firefox. Quitting and restarting FF most often reactivates the icon. Occasionally, the mini-1Password icon in the Finder menu ceases to work as well and computer restart is necessary to recover. No consistency found in scenarios leading up to this situation.
1Password Version: 1Password 6 Version 6.8.1 (681006) AgileBits Store
Extension Version: 184.108.40.206
OS Version: OS X 10.11.6
Sync Type: Dropbox