I reported this about two years ago, as bug #1105873. It has since been closed without any actual resolution, merely being told they’ve reproduced this and sent it to be fixed.
The issue is simple: Normally, if you click on an object in the Scene view, it will select the nearest Prefab parent of that object. For example, if I click on an object like this, the “Catwalk_3x3” root object will be selected:
That’s pretty much always what I want.
However, in HDRP, this behavior breaks when clicking the the backface of some other object. The first thing that happens is that the object whose backface I clicked gets selected. That’s 100% never what I want. If I then click again, it will succeed at clicking through the backface to select the object on the other side. However, instead of selecting the prefab root as normal, it will select the mesh instead:
Most of my levels consist of rooms made in ProBuilder, with inverted normals, so that the player is “inside” the box. This means I’m constantly clicking through backfaces to select objects inside the room, unless I’m extremely careful about where the camera is.
Additional note: This also affects what happens when you middle-click on an object to set focus on it. If you middle click on a backface, that’s where focus will be set. Again, I 100% never want that.
This is all HDRP-specific. In the built-in renderer, clicking on the backface is ignored.
Is there any fix for this coming? I was really hoping this would have been an easy thing to address, since it’s such an annoyance. Is this being tracked somewhere? Again, the bug I reported was simply closed without giving me any sense of where it would be tracked.