Created attachment 542524 [details]
Looks like pbr is doing some sort of command wrapping for unrelated stuff, breaking build for random reasons.
See build.log (bleach doesn't have python3.5, readme does, in the middle of stable chroot migration to python3.6)
can you verify if 4.2.0-r1 works? I'll likely be stabilizing it in the next couple weeks.
Can you test yourself? Downgrading bleach to 1.5.0 while still having html5lib-1.0.1 should do.
those are the versions I currently have installed with no problem :|