Provide warning when linking to private Topic / Category

Currently, when attempting to @mention someone who does not have access to a particular Category or message, Discourse will provide a notification that so-and-so cannot access the message.

I think it would be equally helpful if Discourse would provide the same notification when linking to a Topic within Discourse that is restricted access.

For instance, in a public Discussion area, I attempt to link to a Topic in the Members Lounge. Discourse could warn me, “Hey, most people cannot access this Topic as it is in a restricted access Category. Are you sure you want to link to it?”