Recent crashes of certain multimedia contents (this includes Youtube videos, certain flash games and other applications) in conjunction with Firefox are most probably caused by a recent Flash update and/or a malfunctioning browser plugin such as Real Player.

In order to remedy the problem, please perform the steps mentioned in these Knowledge Base articles:

• Flash Plugin - Keep it up to date and troubleshoot problems

• Adobe Flash plugin has crashed - Prevent it from happening again

• Flash 11.3 doesn't load video in Firefox

Other, more technical information about these issues can be found under these Links:

• http://forums.adobe.com/thread/1018071?tstart=0

• http://blogs.adobe.com/asset/2012/06/inside-flash-player-protected-mode-for-firefox.html

Please tell us if this helped!

The Technical one did help. I tried the new profile creation as well, but didn't solve the problem. Strangely though disabling protected mode helps, buts its not so safe for browsing activities. (By adding ProtectedMode=0 in mms.cfg file) Thanks. But i am still looking for a concrete solution, which doesn't leave my browsing activity vulnerable.

I'm glad that helped but I appreciate your security concerns. It would probably be worth changing Flash to 'Ask to Activate' from the Plugins tab of the Add-ons Manager.

You could also try:

• disable a possible RealPlayer Browser Record Plugin extension for Firefox and update the RealPlayer if installed
• disable hardware acceleration in the Flash plugin

The eventual concrete solution is likely to be to stop using the flash player plugin altogether, although this may be some way down the road. If you experience issues on Youtube specifically then I suggest switching over to html5 for youtube (no need for flash). See here to join the trial:

http://www.youtube.com/html5

You may also be interested in Shumway which is a project aiming to playback SWF (flash) using only html5 and without the need for any plugin: http://mozilla.github.io/shumway/

I hope this helps.