Sequence flow is missed, when drag a new custom element

I’m trying to develop bpmn-js-example-custom-elements

Question

As can be seen in the attached image, custom elements when added by dragging, flow sequence is not created automatically and should be created in a separated operation by user.

But for standard elements, it’s working truly.
I need a hint or an example to know where to start and modify the codes of the example to get my target.

What is the type of your custom element? A connection can only be created if it is allowed according to the rules.

Thanks for replying. What is the type of your custom element?
I have this problem in two places:
1- In bpmn-js-example-custom-elements it has extended a new extension element:

<bpmn2:extensionElements>
    <qa:analysisDetails lastChecked="2015-01-20" nextCheck="2015-07-15">
    </qa:analysisDetails>
</bpmn2:extensionElements>

So, according to the rules and your answer, it is not possible to have auto connection by dragging a new extension element?

2- I have mixed properties-panel-extension and bpmn-js-example-custom-elements, now I have same standard element, with some extra properties bpmn2:serviceTask extra:servicetype="SQL"

  <bpmn2:process id="Process_1">
    <bpmn2:serviceTask id="Activity_1i0sc9v" extra:servicetype="SQL" />
  </bpmn2:process>

Summary: you said A connection can only be created if it is allowed , so why it is allowed when a new element is created by click and why it is not allowed when I create the element by drag? I’m confused.

Untitled

So the problem is drag or element? Could you guide me more? Because I have this problem in both extended element which is creating <bpmn2:extensionElements>, and in standard element with some extended properties <bpmn2:serviceTask extra:servicetype="SQL" />.

Appending a service task to a service task should work regardless of what extension elements exist. How exactly have you modified the code?

Thanks for replying. Try to just download and run bpmn-js-example-custom-elements without modifying anything.

Now when I drag <bpmn2:task id="Activity_10wsf1z" qa:suitable="25"> or <bpmn2:task id="Task_1" name="Examine Situation" qa:suitable="70"> or <bpmn2:task id="Activity_0o0px3g" qa:suitable="100" /> connection is missed. As can be seen in first post of this topic.

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