The Safari 1Password extension has stopped working on my two Mac computers. On both computers it stopped working within the past week. The iMac 1Password stopped last week and the MacBook Pro stopped this week. The Safari 1Password appeared in the Safari Toolbar area but clicking on the icon caused no password window or dropdown list. The1Password icon has since disappeared.
I've tried the suggestions in https://support.1password.com/safari-cannot-install-extension/. I tried installing from the Apple Safari Extensions page I get the Safari can't install this extension model window and Install failed. Please try again later on the web page.
If I download the 1Password-4.6.4.safariextz from https://agilebits.com/onepassword/extensions, I get the same Safari can't install this extension error.
The 1Password mini is running in the Apple menu. Clicking on a login name will launch the correct web page but not fill in the ID or password.
I recently uninstalled the Avast antivirus with the hope that would help. It did not.
Safari is version 10.1 (12603.1.30.0.34)
1Password Version: 6.6.4 664002 - Mac App Store
Extension Version: 4.6.4
OS Version: 10.12.4 (16E195)
Sync Type: iCloud & Dropbox