Crashes or other problems with certain multimedia content in Firefox (such as Youtube videos and Flash animations or games) can often be resolved by performing the steps 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

On Windows Vista and above, you can disable Flash protected mode by following the instructions on these pages:

• http://forums.adobe.com/thread/1018071#TemporaryWorkaround
• http://kb.mozillazine.org/Flash#Disabling_Protected_Mode_in_Flash_11.3

(See this Adobe blog post for technical details about Flash protected mode.)

Please tell us if this helped!

As I had stated in my post. All version of everything is UP TO DATE.

Certain Firefox problems can be solved by performing a Clean reinstall. This means you remove Firefox program files and then reinstall Firefox. Please follow these steps:

Note: You might want to print these steps or view them in another browser.

1. Download the latest Desktop version of Firefox from http://www.mozilla.org and save the setup file to your computer.
2. After the download finishes, close all Firefox windows (click Exit from the Firefox or File menu).
3. Delete the Firefox installation folder, which is located in one of these locations, by default:
   • Windows:
     • C:\Program Files\Mozilla Firefox
     • C:\Program Files (x86)\Mozilla Firefox
   • Mac: Delete Firefox from the Applications folder.
   • Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory.
4. Now, go ahead and reinstall Firefox:
   1. Double-click the downloaded installation file and go through the steps of the installation wizard.
   2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

More information about reinstalling Firefox can be found here.

WARNING: Do not run Firefox's uninstaller or use a third party remover as part of this process, because that could permanently delete your Firefox data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. These cannot be recovered unless they have been backed up to an external device!

Please report back to see if this helped you!

Thank you.

IF it is the same thing, as seems possible, it may be a known issue only affecting some Macs and the work around is to downgrade by using an uninstaller and reinstall the older versions

• ATTENTION MAC CUSTOMERS - Flash Player 13 "Plugin Failure" Workaround
  Apr 10, 2014 4:28 PM http://forums.adobe.com/thread/1447282
  1. Download and run our uninstaller: http://fpdownload.macromedia.com/get/flashplayer/current/support/uninstall_flash_player_osx.dmg
  2. Download and run the version 12 installer from: http://fpdownload.macromedia.com/get/flashplayer/current/licensing/mac/install_flash_player_12_osx.dmg

Note there is now a suitable Release of FlashPlayer 13 the following is from an update to the Adobe thread:

Update 4/16
I'm pleased to announce that Flash Player 13.0.0.201 for Mac is now available from http://get.adobe.com/flashplayer.  This release resolves the crash described in this thread.  As noted above, you can either download this immediately from adobe.com or wait for the update to be applied automatically, within 24 hours, via our recommended auto update mechanism.  If you encounter any problems updating, please visit http://helpx.adobe.com/flash-player.html for basic troubleshooting steps.