Revert to legacy SameSite behavior

Supported on: Firefox 96 or later

Registry

HKLM Software\Policies\Mozilla\Firefox

HKCU Software\Policies\Mozilla\Firefox

Value name: LegacySameSiteCookieBehaviorEnabled

Enabled: LegacySameSiteCookieBehaviorEnabled = 1

Disabled: LegacySameSiteCookieBehaviorEnabled = 0

Description

If this policy is enabled, Firefox will revert to the legacy behavior of SameSite. 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.