Understanding details of build environment

This results in a file of 105M (9M gzipped). If you think it is relevant, I can attach it here (if allowed, on Github, or send it by email). But I found a solution to the problem, that is not dependent on R8. Both apks (from release tag and from master) use version 1.71 of bouncycastle. If I patch both versions to use the current version 1.83, the crash is solved. It seems bouncycastle improved support for r8 in the meantime.