Currently, if Anonymous User cannot view certain Landing Page (because he is not granted permission to do that), then after loading this Landing Page in Landing Page Manager (in Admin UI), the login screen is shown instead of the Landing Page, and the following error is shown at the bottom:

Cannot get page information from the server

After logging in inside the preview, Landing Page Manager works correctly.
The expected behaviour is that the Editor sees the Landing Page right after they access Landing Page Manager, without the need to log in again inside the preview.

Steps to reproduce

1. Create new eZ Platform EE install.
2. Login to the Admin UI as an admin.
3. Navigate to "Admin" -> "Roles" -> "Anonymous".
4. Delete Content/Read policy from there.
5. Navigate to "Page" tab.
6. The login screen and the error described above will be shown.