Digital Rights Management (DRM) is technology that enables online video and audio services to enforce that the content they provide is used in accordance with their requirements. This technology may restrict some of the things you can do in the browser. While some DRM-controlled content can be viewed using the Microsoft Silverlight and Adobe Flash plugins, many services are moving towards HTML5 video that requires a different DRM mechanism called a Content Decryption Module (CDM).

Beginning in version 38, Firefox desktop supports HTML5 playback of DRM-controlled video and audio through the Adobe Primetime CDM. This CDM implements a DRM system called Adobe Primetime, which was previously available via the Adobe Flash plugin.

Firefox downloads and enables the Adobe Primetime CDM by default to give users a smooth experience on sites that require DRM. The CDM runs in a separate container called a sandbox and you will be notified when the CDM is in use. You can also disable the CDM and opt out of future updates by following the steps below. Once you disable the CDM, however, sites using this type of DRM may not operate properly.

Disable the Adobe Primetime CDM without uninstalling

Disabling Adobe Primetime from the Add-ons Manager prevents it from running on your computer and prevents future updates from downloading. To disable the CDM plugin:

1. At the top of the Firefox window, click on the Firefox buttonOn the menu bar, click on the Tools menuAt the top of the Firefox window, click on the Tools menu, and then click Add-ons. The Add-ons Manager tab will open. Click the menu button and choose Add-ons. The Add-ons Manager tab will open.

2. In the Add-ons Manager tab, select the Plugins panel.
3. Select Never Activate on the menu next to Adobe Primetime DRM.

Opt out of CDM playback, uninstall CDMs and stop all CDM downloads

You have the choice to globally opt out of HTML5 DRM playback. Once you opt out, Firefox will delete any downloaded CDMs from your hard drive, cease all future CDM downloads and disable DRM playback. This affects only DRM-controlled HTML5 audio and video. To opt out of HTML5 DRM playback completely, follow these steps:

1. At the top of the Firefox window, click on the Firefox button and then select Options.At the top of the Firefox window, click on the Tools menu and then select Options.On the menu bar, click on the Firefox menu and select Preferences....At the top of the Firefox window, click on the Edit menu and select Preferences.

   Click the menu button and choose Options.Preferences.

2. Click the Content panel.
3. Remove the check mark next to Play DRM content.

You may encounter sites where content playback is not possible without DRM enabled. You may always turn DRM playback on again by opening the OptionsPreferences > Content panel and putting a check mark next to Play DRM content. After checking the checkbox, HTML5 DRM playback will be re-enabled and the Adobe CDM will download automatically.

Supported platforms

Currently, Adobe Primetime is only available in Windows Vista/7/8 and above when using 32-bit versions of Firefox. Mac OS X, Linux, Windows XP and 64-bit versions of Firefox are currently not supported.

Similar opt-out capabilities will be offered on all new platforms where Firefox supports Adobe Primetime.