Revert to legacy SameSite behavior on specific domains

Supported on: Firefox 96 or later

Registry

HKLM Software\Policies\Mozilla\Firefox\LegacySameSiteCookieBehaviorEnabledForDomainList

HKCU Software\Policies\Mozilla\Firefox\LegacySameSiteCookieBehaviorEnabledForDomainList

Options

List (registry values) list - list under Software\Policies\Mozilla\Firefox\LegacySameSiteCookieBehaviorEnabledForDomainList

Description

If this policy is enabled, Firefox will revert to the legacy behavior of SameSite for the specified domains. This means that cookies that don't explicitly specify a SameSite attribute are treated as if they were SameSite=None. If this policy is disabled or not configured, Firefox will enforce SameSite=lax for all domains.