How to write window.Vue.use (pluginName) when developing vue plug-ins with parameters?

want to turn a previously made component into a plug-in, encapsulate it with the following code:

import Mylib from "./mylib"
const lib = {
  install (Vue, o) {
    var ele = ".elClassName"
    if (ele) {
      const Mylib = Vue.extend(Mylib)
      const pluginName = new Mylib({propsData: {
        a: o.a,
        b: o.b
      }})
      setTimeout(() => {
        libName.$mount(ele)
      }, 0)
    }
  }
}
if (typeof window !== "undefined" && window.Vue) {
  window.Vue.use(pluginName)
}

where window.Vue.use (pluginName) must not work, how can I write the parameters an and b here?

Mar.28,2021
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