I have done a update on two of my sites to .12 the other day and as of today I got the message "Warning your browser does not accept script's cookies" when trying to log in to both of them. the 3 I have not done yet are fine so its something to do with the update. I use chrome I did try on IE and they are working fine then so something it not right with chrome, I did try going into setting and trying to play with the cookies in there but nothing. So i'm trying on here if any one has a solution.
Did you upgrade the two sites from CPG 1.5.x to 1.6.12?
Had you used the cookie consent plugin on your sites?