Why is my custom prefix automatically underscored? How do I delete the underscore?

this.updateProperties(this.element.businessObject, 'activiti:assignee', '${loopAssignee}', true);
            const loopCharacteristics = moddle.create('bpmn:MultiInstanceLoopCharacteristics');
            loopCharacteristics.collection = '${assigneeBean.resolveUsersTaskAssignee(execution)}';
            loopCharacteristics.elementVariable = 'loopAssignee';
            loopCharacteristics.isSequential = false;
            const completionCondition = moddle.create('bpmn:FormalExpression',
                { body: '${assigneeBean.analyseParallelCompleteCond(execution)}'},
            loopCharacteristics.completionCondition = completionCondition;
            modeling.updateProperties(this.element, {
updateProperties(elementBusinessObject, attrName, attrValue, isAttrs){
        if (isAttrs){
            elementBusinessObject.$attrs[attrName] = attrValue;
        }else {
            elementBusinessObject[attrName] = attrValue;


How do I delete the underscore?"_1"

Can you please write your question (?) in English?

edit: Thanks.

Please share a running / prototypical example that clearly shows what you’re trying to achieve, what is working and what is not.

Use our existing starter projects to quickly hack it or share your existing, partial solution on GitHub. Provide the necessary pointers that allow us to quickly understand where you got stuck.

This way we may be able to help you in a constructive manner.

Thanks :heart:

You seem to have a diagram with an activiti_1 namespace. What tool was the diagram created with?