- [ ] I have searched the [issues](https://github.com/vueComponent/ant-design-vue/issues) of this repository and believe that this is not a duplicate. ### Version 4.2.6 ### Environment 任何浏览器 ### Reproduction link [https://www.antdv.com/components/popover-cn](https://www.antdv.com/components/popover-cn) ### Steps to reproduce 使用 popover 组件的时候。实现点击打开并且点击空白不关闭气泡,使用mask和maskclosable为false时,控制台会报if错误 ### What is expected? 控制台不报错 ### What is actually happening? 控制台会报if错误 <!-- generated by issue-helper. DO NOT REMOVE -->