This is a bug in Firefox 3 where it launches into full screen mode and completely covers the top and bottom GNOME panels as well as its own title bar. While in this buggy mode Firefox cannot be resized, and can only be closed from within the menu.

File -> Quit

A temporary fix involves pressing F11 which switches you into full screen browser mode and pressing it once again to switch back. Once you close Firefox and restart it however it will continue to have the same issue.

To fix this bug permanently, delete the file localstore.rdf from your Mozilla-Firefox profile which is stored in your home directory. Firefox must be closed in order for this to work correctly.

In your home directory run the following command:

$ find . -name localstore.rdf

./.mozilla/firefox/9m0erq4m.default/extensions.rdf

Close Firefox.

Remove the file that was output by the previous command.

$ rm ./.mozilla/firefox/9m0erq4m.default/extensions.rdf

Restart Firefox.

After restarting Firefox will rebuild this file and your browser should work correctly once again.

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