Font issue
When you toggle "Use OS Font" you get an endless loop of errors in the logs:
[Info : Unity Log] Unable to find a font file with the specified Family Name [AveriaSerifLibre-Bold] and Style [Regular].
[Warning: Unity Log] Unable to load font face for [AveriaSerifLibre-Bold]. Make sure "Include Font Data" is enabled in the Font Import Settings.
Toggling it back does not fix the error, and weirdly even restarting the game doesn't. I had to type in "Arial" in the custom font box to get it to render anything at all and stop the constant flood of log messages. :(
Shadows
Shadows seem to use the same color as the text rather than the shadow color, so it just sorta makes the text bolder and blurry.