Compare infobox HTML with Parsoid & legacy on udm wiki page.
Parsoid's output is missing a <span class="mw-3d-wrapper" data-label="3D"> inside mw:File. I didn't investigate how that wrapper is being generated for a mw:File output. But, that missing wrapper causes a missing CSS application that causes a "3D" overlay in legacy case (which is kind of out-of-place IMO, but that is besides the point for the purposes of this task).