Found some little UI glitches in the Windows Theme.
1. The media buttons in the Artist Picture and Album Color Mix section in compact mode have a white background inside the circles. Which makes the buttons harder to look at compared to the Musicbee3 theme.
Image:
http://i.imgur.com/b1aMCG4.png (see the red circle)
2. Borders glitches out when using the Hide Caption bar option in compact mode. This doesn't occur in Musicbee 2.5 using the same theme. Rebooting Musicbee fixes glitching borders, but those reoccur when turning off the Hide Caption bar option. This glitch also occurs in the Album Color Mix and Big Album sections of compact mode.
GIFs:
http://i.imgur.com/vKDjdn3.gifvhttp://i.imgur.com/78uQfwV.gifv (after rebooting Musicbee 3)
3. If you show the main menu in the caption bar and switch to Theater mode, a part of the main menu caption bar hangs, resulting a white space at the right side of the caption bar.
It's better shown in a GIF:
http://i.imgur.com/QGebKoZ.gifvNote: I have those glitches on Windows 8.1. It might or not occur on other Windows versions.
The Musicbee version is 3.0.5922.