In commit f7678575a5, wm4 chooses to mux
all remaining packets when mp_recorder_mark_discontinuity() is called and
adds a call to mux_packets(). However, it is called only after flush_packets(),
which clears the packets before they can be muxed out. This has no ill
effects per se - recordings end on keyframes, as before - but judging from
his commit message, the intention explicitly was to output the inter
frames, since long GOPs can mean several seconds of missing content from
the output. So, clear the stream packet queues only after the final mux.
Also, flushing can mean both discarding and committing. What a country!