Left parenthesis and bracket nearly invisible in Studio on Mac OS X

When editing a script in Roblox Studio I can barely see the left bracket and parenthesis no matter what zoom level I choose. I’m running at 1920x1280, nothing is scaled, and you can see from the screen shot that this is not my monitor but in the pixel data itself. I haven’t seen this on any other of my mac apps - I checked TextEdit, Chrome, and Terminal just to double-check.

This morning is the first morning I tried using my Mac to use Studio, so I haven’t seen it before, but closing Studio and opening it again did not fix things - it’s been consistent all morning, in every place I tried to edit.

I’m running OS X 10.8.5 (yes, it’s super old) on a Mac Mini with Intel HD 4000