Minor nitpick to myself: The list of packages in my chroot includes eatmydata because at some point I was using it for my archive rebuilds in the past. Maybe I should remove it to avoid confusion, but I don't think it's related with the current failure.
I also have fakeroot installed, but I believe it is not build-essential in trixie anymore. (I've asked sbuild authors about this today in Bug #1100636). (Also as before: I don't think it's related either) Thanks.
