Yesterday my Firefox was upgraded from 12 to 13 and I downgraded it back following this, specifically
4.0+nobinonly-0ubuntu3 (natty). Besides the new version 13, there was only one other selection, my previous version 12. Today, Firefox got upgraded again and so I followed the same steps but instead of version 12(there was only one other version besides 13 again), it must have been version 4 because my Firefox is now version 4 and there isn't the version 12 selection.
How do I get back to the version 12 I had? I don't want 13(some things break on it) and definitely don't want version 4. Thanks!