Text is invisible in some apps in El Capitan I've recently updated my Mac Mini to El Capitan and I am having problem with some of my apps: text is not displaying inside them.
I am facing this issue with at least this apps: GitHub for Mac:

Finder (folder names at the left panel and tags are empty) and Mail app

I thought that it can be the font issue, so I tried to go to the Fonts app and remove all duplicates, remove all fonts with errors and then reboot - no luck, still the same.
What can cause such a behavior?
It seems to be the system-wide issue (I tried to run Finder in Guest user and the issue was still present).
I didn't get this error on my 10.11 mac, try restarting the app, or restarting your computer, it usually fix these kind of problem. If you know how to reproduce this problem, you can report it into Apple Bug Tracker.