It seems that this is a bug in RGBA anti-aliasing. If you change anti-aliasing to grayscale, the bug disappears.
Anti-aliasing settings can be changed in Ubuntu Tweak or in MyUnity under Fonts section.
It seems that this is a bug in RGBA anti-aliasing. If you change anti-aliasing to grayscale, the bug disappears.
Anti-aliasing settings can be changed in Ubuntu Tweak or in MyUnity under Fonts section.