Do not allow preferences to be changed

Supported on: Firefox 60 or later, Firefox 60 ESR or later

Registry

HKLM Software\Policies\Mozilla\Firefox\FlashPlugin

HKCU Software\Policies\Mozilla\Firefox\FlashPlugin

Value name: Locked

Enabled: Locked = 1

Disabled: Locked = 0

Description

If this policy is enabled, Flash preferences cannot be changed by the user. If this policy is disabled or not configured, the user can change their Flash preferences.