Google blocking login for some browsers?

Ive been trying to login to Google services on Firefox with a spoofed Chrome useragent, which I ironically use to prevent Google from degrading search and youtube.

It won't let me get past login screen. Just says to "try a different browser". Has Google started blocking browsers that pretend to be Chrome? Can anyone else replicate this? This is scary, because Google gives crappy versions of many of their sites to non chrome browsers.