Open Sans Chrome and Safari Render bug

The "Open Sans" font for some reason just started looking terrible on both Chrome and Safari (on Mavericks 10.9.2), becoming some super thin and light font. Does anyone know what's up? I tried resetting my font cache, but it didn't work!

See the images below, (1) On Todoist.com (which uses Open Sans), and (2) On Google Docs, where my body text uses the Open Sans font. You can see in the 2nd image, the word "Rhapsody in Red" in the body is Open Sans Italics, which looks vastly different from the regular Open Sans. The problem does not affect the Italics version, only the regular version.

Solution 1:

Try restoring the system fonts using the Font Book.app

Open and click Restore Standard fonts.