gnome-subtitles crashes because of "fatal error in mono runtime"

gnome-subtitles 1.6-2.1 (from repository) works fine on Focal, but crahes on Grooy when opening a video file.

I've tried this both after upgrading to Groovy and on a "clean" install of it.

"Native Crash Report" says:

=================================================================
Got a SIGSEGV while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.

=================================================================
Native stacktrace:
0x5623070cceb5 - gnome-subtitles : (null)
0x5623070cd250 - gnome-subtitles : (null)
0x56230707a129 - gnome-subtitles : (null)
0x56230703ded9 - gnome-subtitles : (null)
0x7fd79e0e3bb0 - /lib/x86_64-linux-gnu/libpthread.so.0 : (null)
0x7fd781ce3bc5 - /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so : (null)
0x7fd781cd4bf4 - /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so : (null)
0x7fd781cbb61a - /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so : (null)
0x7fd781ec95e3 - /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so : (null)
0x7fd781ecd016 - /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so : (null)
0x7fd781ecd29a - /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so : (null)
0x7fd781e9af92 - /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so : (null)
0x7fd7822742b0 - /lib/x86_64-linux-gnu/libva.so.2 : vaPutImage
0x7fd7822f9a14 - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstvaapi.so : (null)
0x7fd7822b79c6 - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstvaapi.so : (null)
0x7fd7822becce - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstvaapi.so : (null)
0x7fd792157c33 - /lib/x86_64-linux-gnu/libgstbase-1.0.so.0 : (null)
0x7fd79215b64d - /lib/x86_64-linux-gnu/libgstbase-1.0.so.0 : (null)
0x7fd792543208 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_query
0x7fd79254396b - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_peer_query
0x7fd7925833c8 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_peer_query_caps
0x7fd79215b32f - /lib/x86_64-linux-gnu/libgstbase-1.0.so.0 : (null)
0x7fd792543208 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_query
0x7fd79254396b - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_peer_query
0x7fd79257d5fc - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd792541b5e - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_forward
0x7fd79258029a - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_proxy_query_caps
0x7fd792541d88 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_query_default
0x7fd792543208 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_query
0x7fd79254396b - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_peer_query
0x7fd7925833c8 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_peer_query_caps
0x7fd792263631 - /lib/x86_64-linux-gnu/libgstvideo-1.0.so.0 : (null)
0x7fd7822b14f8 - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstvaapi.so : (null)
0x7fd792251a66 - /lib/x86_64-linux-gnu/libgstvideo-1.0.so.0 : (null)
0x7fd792543208 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_query
0x7fd792580b38 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_query_caps
0x7fd792251cd1 - /lib/x86_64-linux-gnu/libgstvideo-1.0.so.0 : (null)
0x7fd792543208 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_query
0x7fd79254396b - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_peer_query
0x7fd79257d594 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd792541b5e - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_forward
0x7fd7925800ce - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_proxy_query_accept_caps
0x7fd79254235b - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_query_default
0x7fd792543208 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_query
0x7fd7925835a8 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_query_accept_caps
0x7fd79253bb4a - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd792545ba9 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_send_event
0x7fd79238011c - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstplayback.so : (null)
0x7fd79253a6dc - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd792539ef0 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd7925467bc - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_sticky_events_foreach
0x7fd79238ba2f - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstplayback.so : (null)
0x7fd792389625 - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstplayback.so : (null)
0x7fd79238a17c - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstplayback.so : (null)
0x7fd79238a41e - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstplayback.so : (null)
0x7fd79a3a08fa - /lib/x86_64-linux-gnu/libgobject-2.0.so.0 : g_closure_invoke
0x7fd79a3b3493 - /lib/x86_64-linux-gnu/libgobject-2.0.so.0 : (null)
0x7fd79a3b9c21 - /lib/x86_64-linux-gnu/libgobject-2.0.so.0 : g_signal_emit_valist
0x7fd79a3b9d83 - /lib/x86_64-linux-gnu/libgobject-2.0.so.0 : g_signal_emit
0x7fd79a3a5464 - /lib/x86_64-linux-gnu/libgobject-2.0.so.0 : (null)
0x7fd7924f1e88 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd79a3a749a - /lib/x86_64-linux-gnu/libgobject-2.0.so.0 : g_object_notify_by_pspec
0x7fd79253a5e7 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd792545820 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_push_event
0x7fd79215abf8 - /lib/x86_64-linux-gnu/libgstbase-1.0.so.0 : (null)
0x7fd79215c22a - /lib/x86_64-linux-gnu/libgstbase-1.0.so.0 : (null)
0x7fd782487e96 - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstcoreelements.so : (null)
0x7fd79253ba7c - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd79253c0fe - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd79253c5b8 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd792539ef0 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd792545530 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_push_event
0x7fd7823f2ef0 - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstvideoparsersbad.so : (null)
0x7fd7823f620f - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstvideoparsersbad.so : (null)
0x7fd7921397c1 - /lib/x86_64-linux-gnu/libgstbase-1.0.so.0 : (null)
0x7fd79253ba7c - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd792545ba9 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_send_event
0x7fd79238011c - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstplayback.so : (null)
0x7fd79253a6dc - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd792539ef0 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd7925467bc - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_pad_sticky_events_foreach
0x7fd79238ba2f - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstplayback.so : (null)
0x7fd792389625 - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstplayback.so : (null)
0x7fd79238a17c - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstplayback.so : (null)
0x7fd79a3a3fc1 - /lib/x86_64-linux-gnu/libgobject-2.0.so.0 : g_cclosure_marshal_VOID__OBJECTv
0x7fd79a3a0b56 - /lib/x86_64-linux-gnu/libgobject-2.0.so.0 : (null)
0x7fd79a3b9b9f - /lib/x86_64-linux-gnu/libgobject-2.0.so.0 : g_signal_emit_valist
0x7fd79a3b9d83 - /lib/x86_64-linux-gnu/libgobject-2.0.so.0 : g_signal_emit
0x7fd79251ca20 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : gst_element_add_pad
0x7fd78243a08d - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstmatroska.so : (null)
0x7fd782440981 - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstmatroska.so : (null)
0x7fd782441831 - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstmatroska.so : (null)
0x7fd782445a58 - /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstmatroska.so : (null)
0x7fd7925741c7 - /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0 : (null)
0x7fd79a753b04 - /lib/x86_64-linux-gnu/libglib-2.0.so.0 : (null)
0x7fd79a7531f1 - /lib/x86_64-linux-gnu/libglib-2.0.so.0 : (null)
0x7fd79e0d8590 - /lib/x86_64-linux-gnu/libpthread.so.0 : (null)
0x7fd79dfe3223 - /lib/x86_64-linux-gnu/libc.so.6 : clone

=================================================================
Telemetry Dumper:
Thread 0x7fd780c38640 may have been prematurely finalized* Assertion at mono-threads.c:650, condition info' not met, function:mono_thread_info_current,

All I can say is to report a bug