Newer versions of FFmpeg hang/take a really long time to render

[7x11x13]

Unsure which version makes the breaking change. Somewhere after 4.4 and before 6.1. Possible fixes:

• Bundle prebuilt FFmpeg v4.4 with the application
• Update render commands to work correctly with latest version (if possible)

[7x11x13]

Did some benchmarks, seems like FFmpeg 4.4 and 5.1 work fine, but 6.1 takes ~600x as much time to render

[7x11x13]

Fixed with bb570ca, however older versions of FFmpeg no longer work (videos don't process once uploaded to YouTube)