Web site programmers never cease to amaze me (for the worst). I loaded Fedora 19 XFCE and I'm overall VERY VERY impressed with its speed, there is a notable difference with the previous F18 release (also XFCE).
However, loading the Midore XFCE web browser gives me one unpleasant surprise: twitter.com loads and the entry fields for username and password can't be clicked. I mean, I click on them but the blinking cursor to enter data never appears.
It turns out the twitter code seems to do user agent sniffing and freaks out when it finds out the Midori user agent.
Finally I solved it by going to the Midori web browser preferences, clicking on Network->Identify as->Custom and cutting and pasting the user agent for Firefox 22... (I could probably have gotten around it as well by selecting "Safari", which is also based on Webkit as Midori, but what the ****, I'm lazy, and didn't want to test another option ;).
Just FYI folks... FC