@coolboymew @internetfreak yes. I have three different hdmi input adapters here. I had a vga input adapter but it did not work. I am borrowing an expensive capture adapter that is supposed to work with macos but it doesn't work right but it sometimes works on linux. I just got another cheap 12 dollar adapter today, it doesn't work on macos so trying linux next. it is ridiculous how hard this is.

here's the alleged "manual" for an elgato lol: