My reputation history on SO (and other sites) is completely broken:
I can't open, or close, the expanding rows - clicking on the arrows does nothing here:
When I switch pages (I.e. go to page two, or three, or back to one, or anything), I lose all the disclosure arrows:
It seems to work for me on Meta, but I've heard reports of it being broken for others even on Meta.
Safari 9.0.1 on OS X 10.11.1. Note that I can't reproduce the arrows disappearing on Chrome.