ffmpeg can move the moov atom to the front with -movflags +faststart before the output filename, but yt-dlp knows how to exclude a few small unnecessary atoms. My mpv script adds

-empty_hdlr_name true -use_editlist false -write_btrt false -write_tmcd false

to my ffmpeg commands to exclude some of those unneeded atoms, but occasionally I need to set the editlist option to true for the timestamps to come out right.
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