svg方式渲染折线图时，当数据源的所有数据值相同时，阴影失效，且影响了线条的展示

[liuhui666]

Version

4.7.0

Reproduction link

https://codesandbox.io/s/beautiful-currying-esdpl?file=/src/App.js

Steps to reproduce

打开之后无需操作 直接看到现象

1. echarts.init(dom, null, {renderer: "svg"});
2. series[0].data =[1,1,1,1,1,1,1]
3. series[0].lineStyle={
   shadowBlur: 20,
   shadowOffsetX: 20,
   shadowOffsetY: 20

}

What is expected?

能有一条可见的线条

What is actually happening?

只展示出折线拐点标志，线条没有颜色

---

必要条件是：
1、数据源的所有值一定都要相同
2、lineStyle增加阴影属性

线条的path标签里有style="filter: url("#zr2322-shadow-0");" 导致问题出现

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[Ovilia]

Thanks for reporting. Seems to be a bug.

[ZeyanGuo]

Same issue at version 5.2.2, is there any solution to fix it?
lineStyle: { width: 3, shadowColor: 'rgba(36, 178, 118, 0.3)', shadowBlur: 6, shadowOffsetY: 3, },

[liuhui666]

这是来自QQ邮箱的自动回复邮件。您好，您的邮件我已收到                                        ——刘慧