I use FF at planets.nu ... with version 36.x I was able to select text from a message pane on this site. After updating to 37.0.1, FF don't hightlight text within the message pane. I cannot copy 'n paste the text into clipboard. I read a lot about old "copy 'n paste errors" in former FF versions. I checked the mentioned settings under about:config ... change nothing there. Everything was fine. I checked also, if other browsers are not able to copy n' paste the message content. No problems there. I checked the CSS settings for the HTML structure ... no settings found that prevent copy 'n paste. No idea whats going wrong or where to start the search for a solution.