The granularity of IR columns in APEX 5 is great, but the headers and data start misaligning if you hide a column using CSS.
This is a basic IR on emp, with static region p2_report and static column ID of deptno for the DEPTNO column.

I've hidden the DEPTNO column using
#p2_report #deptno
,#p2_report td[headers='deptno']
{display:none;}
This might have come from a media query looking to hide columns if in portrait, so it still fits on the screen.
This was not a problem in 4.2, is there something we need to be aware of in 5?