Adapter for mounting a GoPro on an external monitor. The monitor: HP LA2205WG [1][2].
I don't expect anyone to own that particular monitor, but the design can be easily adjusted to monitors with similarly shaped bezels.
The GoPro frame used in the second picture is this one: https://www.printables.com/model/202221-gopro-hero-3-improved-top-and-bottom-frame-mounts