I'm wondering how complete those changelogs are.
I was working on some boards this week, and last time i worked on kicad was 4.04, was using 4.06 now. When working i noticed this purple edge around my pads, didn't quite know what it was. When rendering i noticed part of the traces also rendering in copper, but didn't really look at it in detail.
However when making my gerbers i noticed the same thing, that the solder mask holes where quite a bit bigger than the pads. After some googling i found it was a setting (solder mask clearance) that for mysterious reasons now defaulted to 0.2mm rather than 0 in the past versions >_<
Just checked the releasenotes of 4.05 & 4.06, didn't see anything in them about it >_<.
Ah well, i found it and my boards are okay now, but it was a stupid annoyance >_<.
I hope i won't notice many other such strange things when upgrading to newer versions in the future ^^'.