Basically all text on Android.SE and its child meta are showing up as gray when I use Google Chrome, but it appears fine on Firefox.
I'm using Ubuntu.
This is also a problem on Opera:
I use Arch Linux, and have instaled ttf-google-fonts-git. Roboto has always been a part of the package. But the site still looks awful on my computer. When I was typing this as a comment, I couldn't see what I'm typing well enough. Though I can see this just fine when typing in the Answer section.
If you must use Roboto, please use Roboto-Medium or Roboto-Regular instead of thin or light variants. The site is currently unusable for me. And please set up fallbacks for people who don't have Roboto.
Not a real answer to this, but I've experienced this font issue in at least 3 of my Windows 10 laptops/PCs.
Things common to all those PCs, if I remember correctly, were:
Issue was gone once I uninstalled the font family from my system. I suppose it was a Chrome-specific issue where the local Roboto family competed with the Google fonts' online version of it.
This could be relevant to Ubuntu as well.
I use the Web Override extension for Chrome to fix this.
Then just add the following to the CSS tab:
font-family: Arial !important;
p.s. I cannot believe this has not been fixed...