Just happened to me as well. It is working everywhere else, on facebook, on bing searches, and every other site, but it's not working on google! wtf. This has been going on for a while I guess, but I just started facing this issue recently. Damnit, it's such a handy tool for judging keyword competition, tried uninstalling, reinstalling, restarting and everything else! Wonder when they will fix it, or maybe they have intentionally disabled it.