... when upstream element is d3d11. Note that, if upstream element is not d3d11, crop meta is almost pointless since d3d11videosink will upload video frame to GPU memory in any case. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/933>
In order to support d3d11 device update, d3d11videosink will configure window on the first buffer. So, there might not be configured window when propose_allocation() is required. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/933>