[bug report] it is suggested to fix the jitter problem when the browser zooms to 67% when multiple drop-down boxes are selected

[azqasxws]

Element UI version

2.15.2

OS/Browsers version

window10 Google Chrome78.0.3904.108（正式版本） （32 位）

Vue version

2.6.14

Reproduction Link

https://codepen.io/azqasxws/project/editor/AgoMkw

Steps to reproduce

下拉框多选2个选项时候外层发生抖动（特别是谷歌浏览器缩放到90%时候）

What is Expected?

修复抖动问题

What is actually happening?

用户体验

[element-bot]

Translation of this issue:

Element UI version

2.15.2

OS/Browsers version

Windows 10 Google Chrome 78.0.3904.108 (official version) (32-bit)

Vue version

2.6.14

Reproduction Link

https://codepen.io/azqasxws/project/editor/AgoMkw

Steps to reproduce

The outer layer jitters when two more options are selected from the drop-down box (especially when Google browser zooms to 90%)

What is Expected?

Fix jitter

What is actually happening?

User experience