Moving outgoing connection start point from gateway causes default flow to be lost

If a default flow has been set to a gateway, then it’ll be lost when another outgoing connection’s start point is moved away from the gateway. Visually everything will look fine, but in the xml markup the default attribute is lost, and as soon as a forced refresh is done then the default symbol disappears from the canvas as well. See the gif for how the issue can be reproduced.

This is a bug, thanks for reporting.