About ie compatibility using vue-cli3.0

I used vue-cli3.0 to build a vue application, which uses some ui components of iview, because I have been using chrome to develop and debug. Today, the test suddenly said that there was a problem with ie compatibility. I tried it on ie. It is different
as follows:

iviewbabel-polyfillvue-cli2main.jsvue-cli3.0entry:
main.js

vue.config.js

babel.config.js

has always used the command line to build a project directly with vue-cli. I have never manually configured babel myself. Now it is a bit of a mess. I hope you can give me some advice. I would appreciate it

add: IE error always indicates that Error in render: "TypeError: object does not support" findIndex "attribute or method"

Vue-cli compatibility babel

Oct.26,2021

when you encounter compatibility problems under IE11, the related processing is:

productionSourceMap: true, is set in vue.config.js , so that after deployment, you can locate the specific file with the problem by viewing the element in ie, instead of not seeing which one corresponds to the entire packaged file at all. (only after build deployment, which cannot be seen by dev)
after the class library with the problem is found, I have an error that one of the class libraries under node_modules reports es6 incompatibility, which is also set in vue.config.js :
.
```
transpileDependencies: [
   'xxxx'  // babel-polyfill
],
```

my side is solved through the above solution. Don't forget to change the productionSourceMap back after the solution.

first of all, you set the contents of your babel.config.js and modify'@ vue/app''as shown in the following figure

vue.config.jschainWebpack,

Note: about the first step, the documentation in vue-cli3 is very clear. You can take a detailed look at ide/browser-compatibility.html-sharpbrowserslist" rel=" nofollow noreferrer "> document address

Previous: Vscode cannot add breakpoint

Next: The front end draws the flow arrow. Are there any good solutions? Ask for advice