>>720Guess you are looking for 'Touhou_sdm_run_v2', I fixed it way back in 2016 (find it on swfchan). I didn't know about flandre chase though, I just found it when randomly looking here and I was amazed how nobody fixed it after so many years.
BTW explanation time for those interested: in every flash there is a tag FileAttributes, 6 bytes long, 2 bytes at start are the usual type/length, then actual data is 4 bytes, only first byte is used as bitfield, then 3 bytes reserved for future use (that is, never will be used). So that one byte's bitfield controls 8 flags, but ~20 years ago not all of them were used, Adobe added more shit with time. One of the flags is "Uses Action Script 3", which before Flash 9 (which first started using AS3?) obviously wasn't used, and could be left as 0 or 1, wouldn't make difference. But after AS3 was introduced, any old flash (AS1/2) that had this bit as 1, would say "I use AS3", which is a lie and confuses the player.
In case you have other old flashes that you know worked before, but stopped working around, say 2010?, you can easily fix it by opening flash in FFDec, navigate to others -> FileAttributes and change ActionScript3 from true to false.
tl'dr realy but if you're here, you prolly have lots of time to waste anyway.