Customize the left pallette

I can set some palette items,like UserTask,ServiceTask.
But I can not set the intermediate, like TimeEventDefinition. When I drag the TimeEventDefinition, it show error img and I can not create the TimeEventDefinition in canvas.
I do not know which file to set the rules.
Do you have any good ideas?

你好,请问你这个前端怎么做的? 能给源码或者github的项目看下吗? 我也想做一个bpmn在线编排的前端界面,但是不知道怎么入手。

Please keep the communication in English so others can participate.

okay, i’m a new comer here, and want to know how to create a bpmn canvas used bpmnjs at my frontend web application(based on reactjs).

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