The Interrupting attribute shows that the selected shape interrupts the current process flow. When enabling the interrupting option, it will create non-broken lines around the selected shape.

Interrupting applies only to Event Sub-Process, a defined Start Event and a defined catching Intermediate Event…​

interrupting 1

This will create a visual queue on around the shape for a defined Start Event.

interrupting 2

This will create a visual queue inside the shape for a Event Sub-Process.

interrupting 3