Created attachment 763493 [details]
Video with steps to reproduce this bug

Description of problem:
If you activate a gateway in the designer and move your mouse toward to any icon (bounding box is moving together with mouse) then all icons disappear.


Version-Release number of selected component (if applicable):
6.0.0 DR5 (Beta3)

How reproducible:
When you move a mouse if Gateway is active. Others flow elements have expected behaviour.


Steps to Reproduce (see attached video file):
1. activate gateway
2. move mouse toward to any icon

Actual results:
All icons disappear and never show again, even if you return bounding box to its place.

Expected results:
User is able to select any icon from menu.


Additional info:
It seems that event MouseUp is not catched and the designer think that user wants to move a gateway to another place. 
The attached video shows this bug and its workaround. 

Workaround:
1. activate gateway (click on desired gateway)
2. click on the gateway again (be careful about double click)

Results:
User is able to move the mouse wherever he likes. Bounding box and icons are still at the same place.