I am an editor and can read/edit/remove the node "Node 1".
This "Node 1" has 1 relation to another "Node 2" via the attribute "Attribute 1".
The user can't read "Node 2".
In the legacy ezPublish/Platform backend it was like "You are not allowed to view the related object Attribute ( Attribute 1 )" in the "Relations" tab for the "Node 1".
But now in the new eZ Platform 2.5 EE it is an Exception:

HTTP 500 Internal Server Error
An exception has been thrown during the rendering of a template ("User does not have access to 'read' 'content' with: contentId '85943'") in "@admin/fieldtypes/preview/content_fields.html.twig".

So user can't even read "Node 1", because of such strict permission issue.
From our of view, there should not be an Exception or we have to see some Exception listener which will catch such situations and show some user-friendly note and not block the use of seeing the content in the Admin Panel.

Thank you.