Do not allow preferences to be changed

If this policy is enabled, autoplay preferences cannot be changed by the user.

If this policy is disabled or not configured, the user can change autoplay preferences.

Supported on: Firefox 76 or later, Firefox 68.8 ESR or later
Registry HiveHKEY_LOCAL_MACHINE or HKEY_CURRENT_USER
Registry PathSoftware\Policies\Mozilla\Firefox\Permissions\Autoplay
Value NameLocked
Value TypeREG_DWORD
Enabled Value1
Disabled Value0

firefox.admx

Administrative Templates (Computers)

Administrative Templates (Users)