Change Details

"loss of session data" in error messages is meaningless to the user. It basically means "you might have been logged out", and it's normal if the user logged out in another browser window (or logged in, or logged out and logged in as a different user). But it can also happen if the session expired (they're stored for limited time) and MediaWiki isn't sure if it's still the same user who started the edit, so it gives this error instead of just re-creating the session and saving the page, which could potentially expose user's IP address or just attribute the edit to the wrong user. I'm not sure how to clarify, but we should definitely ask the user to check that they're still logged in.