About the message
If Safari can’t install the 1Password extension, you might have another version of the extension already installed or extra copies of 1Password.safariextz on your Mac.
What you should do
To resolve the issue:
- Uninstall the 1Password extension.
- Restart Safari.
- Reinstall the extension from the Safari Extensions Gallery.
Get more help
If you’re still having trouble, remove old copies of 1Password.safariextz:
- Quit Safari.
In Finder, choose Go > Go to Folder. Copy and paste the following path and press Return:
Move all copies of 1Password.safariextz to the Trash.
Empty the Trash.
Open Safari, and install the 1Password extension from the Safari Extensions Gallery.