Steps to reproduce:
- Log in as an user with editor-rights.
- Enable EditWarning ("Warn me when I leave an edit page with unsaved changes" in the editing-tab in your preferences).
- Edit a page in a flagged namespace.
- Leave without saving.
Expected result: A warning should pop up, asking whether you really want to leave without saving.
Actual result: Nothing happens, you just leave the page.
Since it works for non-editors and with pages that can't be flagged this is a bug in FR, probably the beforeunload handler is overridden.
Version: unspecified
Severity: normal