Comment 22 for bug 85833

We are going to close this bug report in what respects to firefox because it looks that it was caused by adobe's flashplugin-nonfree which we can do anything about it, since it is closed source. You might want to report it upstream directly.

Just in case this is still an issue for you, notice that you are not using ubuntu's packaged flash plugin (package flashplugin-nonfree) I recommend you to migrate to the packaged version. It might not prevent those crashes, but the plugin will be always up-to-date by apt the way the other apps are.