Step #5428 "Account page: change your own password" of milestone 497
"Passwords: change your own, and reset it by email". A Password section
in the page's one form, for local accounts: current, new, again. Blank
keeps the password; a new one signs out every other browser
(sessions_since) and keeps this one. A wrong current password counts
toward the login throttle. Audited as account.password_changed.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
