How did the changes in the binary test files tests/files/bad-3-corrupt_lzma2.xz and tests/files/good-large_compressed.lzma, and the makefile change in m4/build-to-host.m4) manifest to the Debian maintainer? Was there a chance of noticing something odd?

https://optimizedbyotto.com/post/xz-backdoor-debian-git-detection/