Not sure if this bug appears in any other admin themes but it's quite bad in Rubik. The behaviours admin tab for a map is severely broken in Rubik, with only a handful of behaviours showing off and the rest seemingly being cut off. They do not display as show/hide fieldsets either but a terribly laid out array of checkboxes and text fields. When I switch to Seven everything looks perfect.
Here's a screenshot of what it looks like in Rubik. I'm not a front end dev so wouldn't have a clue where to start diagnosing this issue.