More weekly password change
The issue in https://yahoo.uservoice.com/forums/600772-new-mail/suggestions/47493353-stop-weekly-password-change persists.
I've disabled K-9 mail - and still Thunderbird gets de-authenticated and demands that "because accounts like yours are targeted" and/or "unusual activity detected". I must again change my password. And then I get told to enable 2FA -- or "remind me later". No option to NOT enable 2FA. Which I was happy to do - until I realized that enabling it is what started this downward slide.
This is really, really painful. As noted previously, this is not increasing my security. And not telling me WHAT THE ISSUE IS, doesn't get it fixed. Continually changing my password on 3 devices (and in two places - web and thunderbird on two of them) isn't fixing any problem. Just wasting my time.
If you told me WHAT, EXACTLY is happening, it could be addressed.
Otherwise, I guess I'll have to find all people/subscriptions that use my Yahoo! e-mail and switch them to another service. That will solve my problem. But not anyone else's. I've used Yahoo! for a VERY long time; I'd prefer not to go there....

If there's something unusual about your sign in or recent activity, we'll ask you to go through another verification step after you've entered the correct password. This is an important security feature that helps to protect your account from unauthorized access. You may be prompted to get a verification code on your Yahoo app, recovery phone number, or recovery email address for any of the following reasons:
- Yahoo notices suspicious account activity.
- You're using an unfamiliar browser or device.
- You're traveling away from your usual location.
- You sign in while using a VPN or a proxy server.
- You've logged in with a private or incognito window.
- There are many attempts to sign in with incorrect passwords.
- The "First time signing in from this device" message appears.
- You've cleared your browser history or data cache including cookies.