How do I disable form autosubmit?

That's very interesting. We've definitely been seeing reports of this issue, but I haven't heard of the extension disappearing while actively browsing Safari. When this occurs does the extension disappear from the toolbar / Safari's list of extensions in Safari preferences?

The extension remains around, but the in-page autofill menu stops functioning.

Close! Safari is actually the one browser where we're explicitly not reaching out to the browser extension to perform fills right now, instead relying entirely on accessibility-based filling (when using CMD + ). This is due to some challenges we've had getting the Safari extension to quickly and reliably perform actions when requested by the desktop app. We're actively working on this issue and we hope to be able to use the Safari extension to perform fills when using CMD + \ in the future, just like every other browser.

Yeah, this is the conclusion I came to in my later posts. It's nice to have confirmation that this is, at least at present, intentional. Gently, I would like to suggest that the promotion of 1Password 8 to GA perhaps should have waited until this issue was resolved. At present, the user experience with Safari is significantly worse with 1Password 8 than with 1Password 7, and I suspect that the plurality of users on macOS use Safari as their browser.

I would strongly recommend some form of public acknowledgement of the state of things with Safari and that the UX is being actively worked on, either in a new thread or in the app or both. Absent this, newly-upgrading users will continue to be surprised by the seeming regressions in UX, and there is significant risk that they will write off 1Password 8, or even 1Password entirely, as a failure.

I appreciate that there are a lot of things at play, and indeed there was a lot of impressive work done for 1Password 8, not the least of which being the fact that it's a complete rewrite. That being said, the fact that it was launched on Mac with the system's default browser not having UX parity with either 1Password 7 or other browsers is somewhat troubling, and it's worth evaluating why that decision was made.