bug489729 (Disable detach and tear off tab) is a workaround for bug 489729 - clicking a tab once and then moving your mouse in a downward motion causes a new window to open.
Provided options (If you want):
1. Disabled the detaching of the tab completely.
2. Enable to create Shortcut on the desctop/explorer.
If you want to undo detach and tear off tab, try "Undo Detach Tab" extension (https://addons.mozilla.org/en-US/firefox/addon/12689/).
· Mozilla Firefox
What's New in This Release: [ read full changelog ]
· Fixed undeclared variable to use.