In the changes toolwindow, I open the differ window on a ".Targets" file. Diff says it's binary (why? it's an unknown file type for IDEA, it could just as well be text). I open it in the editor, and I'm asked to pick a file type for the "*.Targets" files. I choose XML. After that, some of such files are diffed (those that have the "added" status in the changelist), but some other files fo the same type that are "modified" still show the "binary versions..." error, even though the editor opens those files as XML. After IDEA restart, the error usually goes away.