If you find blurry or stretched theme images, please report them here.
Please, do not approve more monstrously stretched themes like these
window buttons don’t display correctly with any theme.
any size window
un installed and re installed firefox
Dude, I’m having the same problem and it is really annoying. Hope they update the software soon.
Firefox 40 has some theme fixes for Windows 10. Please update and see if there are any problems still present.
Sorry, my bad on those two.