combo折叠后所有连线并在一起变成很粗的线不美观 #3712

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Reproduction link

https://codepen.io/cometor/pen/MWwNVdm

Steps to reproduce

示例里我只建了两个节点, 线就很明显变粗了, 我试过了, 如果加更多的节点, 线太粗了, 非常不美观. 请问有什么配置可以在combo折叠的时候只显示一条线么

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