import JQuery from 'jquery'
window.$ = JQuery

or simply

import $ from 'jquery'

mounted () {
   // Your JQuery code here
}
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Vue.prototype.$ = $;

....

// in Vue Component
created() {
  const $body = this.$('body');
  console.log($body);
}

--------------------------------------------

https://webpack.js.org/plugins/provide-plugin/

new webpack.ProvidePlugin({
  $: 'jquery',
  jQuery: 'jquery',
});


--------------------------------------------

https://vuejsdevelopers.com/2017/05/20/vue-js-safely-jquery-plugin/


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