Does anyone know if there is actually a lack of video decoding acceleration on non metal Macs. I have a MacBook Pro 7,1 I plan to upgrade I'm currently on Mac OS 10.14.6. If this is true then let me know. I know for a fact that I had to replace AppleGVA.framework from High Sierra to get video accelerated decoding for quicktime on Mojave. I hope that that's all I have to do on Catalina as well. I saw this a while back when looking into the issue
macOS 10.15 Catalina on Unsupported Macs
You can use the macOS Catalina Patcher to download 10.15.1 then create a new patcher with the current macOS Catalina Patcher or use the install to the machine method
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