**Steps to replicate the issue** (include links if applicable):
* Delete the `loginnotify_prevlogins` cookie (or wait until it expires)
* Go to Special:Preferences and click Change Password
* You are asked to log in with your existing password, even if you have an active session
**What happens?**:
Login-Notify sends you an email saying "Someone (probably you) recently logged in to your account from a new device."
**What should have happened instead?**:
No email is sent.
**Software version** (skip for WMF-hosted wikis like Wikipedia):
**Other information** (browser name/version, screenshots, etc.):
This happened to me today when I changed my wikitech password. Wikitech seems to set a 6-month expiration for the `loginnotify_prevlogins` cookie, while enwiki seems to set a 2-year one.
I could reproduce the issue by deleting the cookie `loginnotify_prevlogins` then clicking on "Change password" again.