This was causing a memory leak in cases like `gltestsrc ! gltransformation scale-x=0.5 ! glimagesink`. Parent meta was being added in assumption that those buffers are different, which was not the case here, creating a reference loop and never freeing the buffer. Co-authored-by: Matthew Waters <matthew@centricular.com> Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5445>