Zstandard version 0.5 (and all other versions < 0.8.1) were pre-releases where forward compatibility was never intended. However, Zstandard is still backward c

Zstandard version 0.5 (and all other versions < 0.8.1) were pre-releases where forward compatibility was never intended. However, Zstandard is still backward compatible with versions down to version 0.4. All releases since August 2016 have been forward and backward compatible. It is unfortunate that Xenial picked up version 0.5, but Yann Collet worked hard to get version 1.3.1 backported for this exact reason https://bugs.launchpad.net/ubuntu/+source/libzstd/+bug/1717040 https://bugs.launchpad.net/ubuntu/+source/libzstd/+bug/17170....