Description of problem
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When more than workflow patterns is added to the editor then the editor will stop accepting input.

No more activities can be added no control commands can be used. E.g. Screenshot1.png shows what happens on Ctrl+a.

How to reproduce
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1) add 'MI Without Synchronization'
2) append 'Implicit Termination'
3) try any other operation (e.g. ctrl+a, mouse multiple select, etc.)