Just moved on UE5.3 and find some bug I guess. See the video. When I use Constrain Aspect Ratio any Trace by Channel is causes screen shift.
Fortunately it happens only within editor viewport when you have that black borders.
I just encountered this same behaviour. It offsets the game view in the viewport area, seems like its to the left and up. Any answers or fixes to this?
The bug is reported Fixed in 5.4, here: https://issues.unrealengine.com/issue/UE-199454
But I still see it in 5.7.3! If you have the Camera set to Contrain Aspect Ratio and you size the PIE viewport so that it is wider (or higher) and then you trace a line from the camera to a cursor (you shoot from the camera), the LineTrace in 3D world works OK, but the DebugDraw draws the line with offset.
Hope Epic can re-visit this, it is annoying.