Installed it on a MacBookPro8,2 late 2011 15. Sleep/Wake/Brightness are working, but I'm not able to load the AMDRadeonX3000.kext post-boot, in an attempt to get better thermal condition.
The late 2011 MacBook Pro as a problem with the GPU and to bypass it, I used this solution in High Sierra :
https://apple.stackexchange.com/questions/267581/gpu-problem-boot-hangs-on-grey-screen/295805#295805
some discussions about it here :
https://forums.macrumors.com/thread...ed-gpu-efi-variable-fix.2037591/post-27852775
and here:
This guide https://apple.stackexchange.com/a/295805/156133 is working fine on High Sierra. On Catalina installed with dosdude1 patcher (http://dosdude1.com/catalina/) I couldn't make it through,
apple.stackexchange.com
It seems that the AMDRadeonX3000.kext included in the legacy video patch is "broken" ? Any idea about that?
I can confirm that the kext provided by dosdude1 in his Catalina installer works fine.
I had the same problem, so I went digging a little to find Catalina has two extensions folders now. I'm not sure if one is just a remnant from the previous installs (upgraded from Mojave) or what, but because Catalina now has two partition (a read only system partition and a read/write data partition), I had to do a somewhat inconvenient workaround to get the loginhook to work again.
First, go to finder and check /System/Library/Extensions/ to check to see if the AMDRadeonX3000.kext is present there. That is in the read only partition, so if it's there, you're going to have to create the Extensions-off folder, copy the AMDRadeonX3000.kext from Extensions to Extension-off and then delete the original from the regular Extensions directory. I had to do this using the High Sierra partition I kept for just in case something on these non supported systems ever messed up because doing it in single user mode as those instructions said just came up with a permission denied error.
Once I moved the kext, I did the usual boot in single user mode, mounted the drive (/sbin/mount -uw /) and just touched the Extensions directory. My temps went from 80+ degrees to ~65 degrees idle.
As for the force-iGPU-boot.sh file, I just copied that to the Catalina root directory from High Sierra at the same time as I moved the kext. So far, so good. The system has been pretty rock solid so far, but I'm afraid many apps are going to start requiring Metal or having blank elements like the latest release of FCPX. It just has a blank preview screen when editing which is pretty important for a video editor.
Now I have two Extensions directories out of fear of the system actually needing the one in /Library/Exentions/, but that hasn't affected system performance or given any errors so far.
I hope that helps!
Edit: Sorry, I just wanted to clarify something. The loginhook from those instructions points to /System/Library/Extensions-off/ in order to load the AMDRadeonX3000.kext, but when I upgraded from Mojave, the Extensions-off folder I had created was moved to /Library/Extensions-off/ which is why it wasn't working. The new location of /System/Library/Extensions/ is on the read only partition while the /Library/Extensions/ folder is in the Catalina-Data read/write partition. You should be able to re-write the loginhook to just point to the new directory, but I didn't. Come to think of it, that might have been easier.
