Configuration View "Basic": Options "invalid users","valid users","admin users","read list","write list" are visible but empty. When entering a value for any of these options (and committing) this option is not visible any more. The only way to get it back is to switch to advanced mode and deleting the value. (The entered value could be anything, such as simply "abc".)
This bug is still present in 3.6.5
swat is removed in 4.1