I went through the forgotten-password flow on patreon.com, where I already had a password in 1password that wasn't working for some reason. I clicked the link in the do-you-really-want-to-reset email from Patreon, accepted the new password suggestion from the Firefox 1password extension, and answered yes to its “Update password?” question, and the reset-password operation worked just fine. But my 1password entry for Patreon had now had the username (my email address) overwritten with a GUID. Not the password I was setting, and not a GUID that I'm aware of being used anywhere else. I'm guessing it's an underlying account ID that's present in a hidden field in the patreon.com web form, and the 1password extension mistook it for a changed username.
1Password Version: 7.6
Extension Version: 1.21.0
OS Version: macOS 10.15.5
Sync Type: 1password.com
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