On this page Mac OS Windows Applies to: Flash Player 10 Flash Player 11 Mac OS Choose Firefox > Tools > Add-ons. Open the Add-ons dialog box. Select Plugins. In the list of Add-ons, look for Shockwave Flash (another name for Flash Player) and check the status that appears to the right of the plug-in name. Shockwave Flash is disabled. Select Always Activate. Enable the plug-in. Close the dialog box. Windows Choose Firefox > Tools > Add-ons. Open the Add-ons dialog box. Select Plugins. In the list of Add-ons, look for Shockwave Flash (another name for Flash Player) and check the status that appears to the right of the plug-in name. Shockwave Flash is disabled. Select Always Activate. Enable the plug-in. Close the dialog box. Twitter™ and Facebook posts are not covered under the terms of Creative Commons. Legal Notices | Online Privacy Policy