Hi guys, I recently noticed a minor but a little disturbing problem related to some file's icons. When I open Numbers and created a new sheet, the little file icon near the filename on top of the Numbers window turns to be a white paper. Please take a look at my screenshot and another screenshot I found on Google; usually the file icon should be like a grey paper with a Numbers mark on it. All my Numbers files are correctly displayed in Finder. Previously when I updated OS X Yosemite on another MacBook Pro, I got the same issue on Microsoft Word (.doc file icons not displayed correctly in the app). I guess it is related to OS X icon caches or so...Does anyone have the same problem? Or this is just a common case for everyone? Thanks ahead.