Disable Update
Supported on: Firefox 60 or later, Firefox 60 ESR or later
Registry
HKLM
Software\Policies\Mozilla\Firefox HKCU
Software\Policies\Mozilla\Firefox Value name: DisableAppUpdate
Enabled: DisableAppUpdate = 1
Disabled: DisableAppUpdate = 0
Description
If this policy is enabled, the browser does not receive updates. If this policy is disabled or not configured, the browser receives updates.