Margins on normal flow content with forced breaks are incorrectly computed (seem to be MAX_INT?) when floats are around. See attached file. The two blue & green squares should both be visible, either in the same region or in different regions (this behavior is not clearly specified yet).
Created attachment 218005 [details] Test-case
This was broken in WebKit Nightly r158804 but is working correctly in r159991.
Still needs investigation, we want to know what happened.
CSS Regions were removed in Bug 174978.