Authentication.loggedIn() return false in Preview mode. Why?

In development, both showed different results on masterPage.js. Why
console . log ( wixUsers.currentUser.loggedIn ) - true
console . log ( wixMembers.authentication . loggedIn ()) - false

When preview site in development, the site is logged with the author/owner account. The authentication should have return TRUE for loggedIn() but it didn’t. Why?

As i know on Wix-Editors-PREVIEW, there is no permission-check.
On LIVE-SITE, the permission-check is activated.

At least you privide maybe not enough INPUT, maybe this is why you are already waiting more then 1-month for a reply.