I quickly re-packed .tar.gz into xz and renamed libaom patches accordingly. It seems to work with ffmpeg-4.4.

Phyllis, can you test (may be next month?) if libaom-3.2.0 still works on both new and old distros (as you use them for appimage build)?

Andrew,

Tried about 6 times on ubuntu16 but obviously I am doing something wrong. Yes, I changed configure.ac from 3.1.1 to 3.2.0 and the 2 patches were renamed that way too. I think I must have incorrectly repacked from tar.gz to xz still.