[wp-testers] Dashboard issues

[EvitaDesign]

Just upgraded my blog from 2.6.1 to 2.7-RC1-10041.
First it works like a charm but after some logins/logouts the dashbord 
messed up. Now I´ve now screen options, tags box and slug box don´t 
appear and the small menu arrows don´t work.

For me it seems there is a javascript problem. I´ve also tried to 
deactivate all my plugins (+ clearing cahe), but this did not help. 
´Dashboard is broken in FF, IE, Opera and Chrome (all latest version).

Anyone else with such problems or maybe a solution?