Do not prompt for authentication if password is saved
Supported on: Firefox 60 or later, Firefox 60 ESR or later
Registry
HKLM
Software\Policies\Mozilla\Firefox\Proxy HKCU
Software\Policies\Mozilla\Firefox\Proxy Value name: AutoLogin
Enabled: AutoLogin = 1
Disabled: AutoLogin = 0
Description
If this policy is enabled, Firefox will not prompt for proxy authentication when a password is saved. If this policy is disabled or not configured, Firefox will always prompt for proxy authentication.