Symptoms

In a newly created list, after following the default link to a worklist item, either from the task email or from the K2 Worklist task, the scroll bar doesn't show. As a result, the bottom of the display form doesn't appear, which hides the Edit button, which we need.
 

Diagnoses

The reason for the vanishing scroll bar is currently unknown.
 

Resolution

By adding new buttons to the form and configuring them with the rules of the out of the box buttons and then hiding those we managed to resolve this error.