a-cascader 在设定 showSearch 可查询情况下，ant-cascader-picker-label 无法正常显示，添加样式 z-index:1 后可以正常显示。

[lisj168]

• I have searched the issues of this repository and believe that this is not a duplicate.

Version

1.4.0

Environment

"mac":"Catalina 10.15 (19A583)"、"chrome":"77.0.3865.90"、"vue": "^2.5.22"

Reproduction link

https://vue.ant.design/components/cascader-cn/#components-cascader-demo-search

Steps to reproduce

下拉选择完成后，当前选择结果没有正常显示Label框中。

What is expected?

正常显示Label框中

What is actually happening?

Label框中没有内容，在 html 有选中结果内容

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[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.