Version 6.1.1.6
Just purchasd StreamFAB and I am unable to download any 4k content. I never get the option. And yes the content I am trying to grab has 4k. (HBO Max - 'The Last of Us', Disney+ - 'The Mandalorian', AppleTV - Tetris, etc). The only option that it get is up to 1080p. Even if I connect my laptop to a 4K OLED TV.
With AppleTV I never get an option for video on anything I try to download. The only options I get are "audio" and "subtitle". And when I click download just to see, it downloads in 360p.
Any help is greatly apprectiated.
agon024
Just to be clear....     StreamFab could only download 4K from HBOmax  which has limited 4K content available,  see -> 
https://help.hbomax.com/us/Answer/Detail/000001167       While changes to Hulu recently allowed 1080p, I don't recall if 4K was possible.  If it was, it was for only original content, and I don't know if its still possible (I don't download from Hulu that often).   The dvdfab.cn web site for StreamFab is pretty accurate on its capabilities, and NOT mentioning 4K for anything but HBOMax.     If you purchased StreamFab from other sites, I can't comment on those. 
As mentioned,  DRM is a "cat and mouse" game.     The Streaming services try to block apps like StreamFab from downloading and decrypting,  and apps like StreamFab try to break and work around it.     SO you might find sometimes you can download at the full and expected resolution, and other times not.  For more read -> 
https://forum.dvdfab.cn/forum/software-support-english/youtube-to-mp3-youtube-video-downloader/404024-streamfab-faq     while a little out of date (the  issues caused by the streaming services changing DRM  12/2021 had been fixed since then, so the 5.0.0.8 and 5.0.0.9 work arounds have been removed for some time), the general idea is still valid. .