So you have an older PC, you install Linux Mint 9, 10 or 11 and then you try to rock out to your favourite geekgasm on youtube/youporn. What happens? Sweet FA, that’s what. Where flash should be you see nothing.
You go in to About:Plugins in FireFox/IceWeasel/Chrome/Chromium and they all say Flash is installed. A quick look for libflashplayer.so and voila, it’s all there. So why doesn’t it work? I have no clue either, it’s a mystery. Flash player 11 is borked on these systems.
Quick fix, aptitude remove any flash player you have installed, whether it be flashplugin-nonfree, adobe-flash or the alike. Install plain old Mint-flash and it’s working again!
I’m not sure what causes it but newer flashplayers aren’t compatible (probably kernel dependency or some such) but at least now you can sit back with your box of kleenex and enjoy the show.