IORegistryClone VS iina

First of all make sure you have a backup of your current EFI then try some patching. Then grab a copy of IOReg and open it. Search for iGPU entry and locate entry (eg. AppleIntelFramebuffer@0 in my case) with a child “display0” it controls the physical display. Select that entry (eg. AppleIntelFramebuffer@0) and on the right panel locate connector type. Then check if it’s set to “00 08 00 00” or not. (This is the connector type for HDMI). If not then. Leave it as it is (in case of laptops it is mostly 02000000). Then open your config.plist in propertree and head to DeviceProperties -> Add -> PciRoot(0x0)/Pci(0x2,0x0). Then add these entries here (Don’t touch anything already present there just add these) “framebuffer-patch-enable = 01000000”, “framebuffer-conX-enable = 01000000” and “framebuffer-conX-type = 00080000” [IMPORTANT: make sure X in conX is the number you’ll find in the ending of AppleIntelFramebuffer@ which you located previously and make sure it has a child “display0” this is important (in my case=0)] and save the config.plist and reboot. Your HDMI port should be working now. Not 100% sure about it but it works most of the time.

IORegistryClone - https://github.com/khronokernel/IORegistryClone

IORegistryClone - Utility to browse IO registry with a GUI interface, it can be useful for patching features such as CPU power management, USB mapping, etc

Do you have IORegistryExplorer ?

9. IINA

While QuickTime Player is still supported, it's not in a good state imo. I've never found chapters to work, for example, and have had other issues like the app complaining about being "busy" when trying to trim a video. If you're willing to explore, I'd suggest trying out IINA instead. It doesn't support editing, but it's good at playing.

Well, there is not much for Mac, there is this https://iina.io

IINA - Price: Free Modern media player for macOS that supports almost all video and audio formats.

This has been my go to for years: https://iina.io/

IINA - media player.