Hi,
I have made few modifications to the default stencilset_bpmn.json.
Have moved few properties, from propertyPackages to hiddenPropertyPackages in stencilset_bpmn.json for Service task stencil. One of those property packages is multiinstance_typepackage.
But after this change, I can see the image of service task is changed, 
Is there anyway I could avoid this additional symbol from appearing on service task?
Similar behavior happens for isForCompensation checkbox in the service/user task.
Ideally, when the checkbox for isForCompensation is checked, the flag’s value becomes true and the symbol appears on the task.
But if the property is under the hidden properties section and its value is also false, then not sure how this symbol appears on tasks.
Okay so for now, I’m able to get rid of the symbols appearing on service/user tasks. Basically, I have modified the SVG document in stencilset_bpmn.json for stencils user task and `service task.
The modification is to comment out the tags of parallel, sequential and compensation in SVG doc.
Just not sure, if this is the best way to get rid of those symbols or if there’s I’m doing any bad practice
The fact that these symbols are appearing means you removed a property that was controlling that. If you don’t need those, it’s better to keep them on the stencil, but set them to hidden/not visible (nor sure how the property is named from the top of my head).
Thanks for the reply Joram. Yes I have set them to hidden.