Hello J4rm4n, @klhsa9acsb, @MelissaAW. We've followed up with the development team about this. I don't have any information to share at this time when a fix will be available but it is on our list. Thanks very much for you patience here and I'm sorry for the trouble.
J4rm4n
The only reason I can think of for the NYT credentials to be suggested there is that I have used them before to log into the NYT website through Google News
I think your guess is precisely right here. Unlike browsers, apps and most in-app browsers don't distinguish between different sign in pages. So, even though you're on The Guardian, 1Password just sees Google News and will suggest Logins used with Google News. You can open your New York Times item in 1Password and check for a Google News app link to confirm.
If you prefer to sign into news sites through Google News you can delete the Google News app link in your New York Times item then tap Open 1Password > search and select your item > Fill Once. This takes extra steps to sign in but helps ensure the wrong Login isn't inadvertently selected.
Alternatively you can add a Google News app link to other items by tapping Open 1Password search and select your item > Fill & Update Login. This option will require additional caution to ensure you select the correct item from the drop down.
@klhsa9acsb, thanks for letting us know this workaround has helped. Between your keyboard, browser and device settings is there a specific combination that works or doesn't?
@MelissaAW, very interesting that it has been caused by certain adaptive brightness or theme settings! I don't think the 1Password diagnostics would capture anything useful in this case but if you see a specific combination that causes the issue I would be happy to pass that along to the developers.
Thanks again everyone!