I just updated from Q2 2014 to Q3 2015 and run into a strange artifact.
I've styled the RadComboBox using a custom style sheet(RadComboBox_CUSTOM) and a custom image (rcbSprite). In the new version of Telerik all RadComboBox items now looked as they where focused by default - but not according to my CSS file, instead it seems to be a defallt background positioning).
I have tried to look what has beaked since last version we had, but cannot find anything. I've created a small test project for this issue.