When using \documentclass[sigconf,letter]{acmart} I noticed that without regard for the text (I tried different nudges), latex always leaves a space of a couple line-spaces on the end of the right column. I deactivated some directives according to How to remove conference information from the ACM 2017 SIGCONF template?. The space varies depending on the sentence structure above, but it never goes away.
Where could that come from and how do I troubleshoot this?
