{ -brand-name-firefox-relay } will store the websites where you’ve used your email masks, and label your masks with those websites so you can easily identify them. Turning this off means you won’t be able to see where you’ve used each mask, and your account names will no longer sync between devices.
{ -brand-name-firefox-relay } 将存储您使用过马甲邮箱的网站，并以这些网站标记您的马甲，方便您分辨。关闭此功能后，您将无法看到马甲在何处使用过，并且您的账户名称也将不再在设备之间同步。