If the number of modules spans over 2 lines, ugly overlapping of controls may occur.
Applies to Redmine 1.0, 1.1, 1.2
This happens for Alternate and default theme.
If you have alot of modules installed and do not have widescreen real estate, as you resize the width of the window and the modules span over the second line, overlapping of controls may occur.
Classic theme do not have this behaviour.
Workaround is to use Classic theme as of now.