Just reset that option. Now they are just darker solid gray squares in Firefox and IE. When you hover over them, they are different colors (facebook is blue, google + is dark orange) but still no detail of what the icon is about. (the Alt text does appear when hovering).
In Chrome, the icon detail is there, but very faint. Once you hover over the icon it turns to what the icon should look like but the icons certainly don’t stand out as something a user would look at.