Comment 17 for bug 144042

I can confirm that this is a bug in ubufox. I got the exact same condition when there was the update from flashplugin-nonfree 9.0.48.0.2+really0ubuntu12(gutsy) to flashplugin-nonfree 9.0.48.0.2+really0ubuntu12.2 (gutsy-updates).

The only way to fix it for me was to shut down firefox, then uninstall flashplugin-nonfree 9.0.48.0.2+really0ubuntu12(gutsy) with synaptic (I assume straight apt would have worked) and then reinstall flashplugin-nonfree 9.0.48.0.2+really0ubuntu12(gutsy) and update it to 9.0.48.0.2+really0ubuntu12.2 (gutsy-updates) within synaptic.

Then when I started firefox and visited youtube, I got the message that I needed to install a plugin which lauched ubufox and it showed that the adobe flash player was installed.

Then I relaunched firefox and everything worked fine.