I assume this is a shoulder strap bracket. I know there were complaints about the curtain rod bracket, so maybe this was added to avoid it. However, that is quite far away from the usual position and moves the anchor point behind the keyboard. I guess your right shoulder strap will now be shorter and more straight, whereas the left strap will now be longer and more angled.
Has anyone seen this before? Would there be any advantages to having that? Or is there a specific reason for doing this?