title: Vue 3 in iOS 9: Unexpected keyword 'const'. Const declarations are not supported in strict mode
body: <p>My Vue 3 app doesn't work in Safari 9. There is this error in console:</p>
  <pre><code>Unexpected keyword 'const'. Const declarations are not supported in strict mode.
  </code></pre>
  <p>My package.json:</p>
  <pre><code>{
    &quot;name&quot;: &quot;test&quot;,
    &quot;version&quot;: &quot;0.1.0&quot;,
    &quot;private&quot;: true,
    &quot;scripts&quot;: {
      &quot;serve&quot;: &quot;vue-cli-service serve&quot;,
      &quot;build&quot;: &quot;vue-cli-service build&quot;,
      &quot;lint&quot;: &quot;vue-cli-service lint&quot;
    },
    &quot;dependencies&quot;: {
      &quot;@babel/polyfill&quot;: &quot;^7.12.1&quot;,
      &quot;@babel/preset-env&quot;: &quot;^7.12.1&quot;,
      &quot;@babel/runtime-corejs2&quot;: &quot;^7.12.5&quot;,
      &quot;axios&quot;: &quot;^0.21.0&quot;,
      &quot;bootstrap&quot;: &quot;^4.5.3&quot;,
      &quot;core-js&quot;: &quot;^3.6.5&quot;,
      &quot;vue&quot;: &quot;^3.0.0&quot;,
      &quot;vue-axios&quot;: &quot;^3.1.3&quot;,
      &quot;vue-slider-component&quot;: &quot;^4.0.0-beta.3&quot;
    },
    &quot;devDependencies&quot;: {
      &quot;@vue/babel-preset-app&quot;: &quot;^4.5.8&quot;,
      &quot;@vue/cli-plugin-babel&quot;: &quot;~4.5.0&quot;,
      &quot;@vue/cli-plugin-eslint&quot;: &quot;~4.5.0&quot;,
      &quot;@vue/cli-service&quot;: &quot;~4.5.0&quot;,
      &quot;@vue/compiler-sfc&quot;: &quot;^3.0.2&quot;,
      &quot;babel-eslint&quot;: &quot;^10.1.0&quot;,
      &quot;eslint&quot;: &quot;^6.7.2&quot;,
      &quot;eslint-plugin-vue&quot;: &quot;^7.0.0-0&quot;,
      &quot;sass&quot;: &quot;^1.28.0&quot;,
      &quot;sass-loader&quot;: &quot;^10.0.5&quot;
    },
    &quot;eslintConfig&quot;: {
      &quot;rules&quot;: {},
      &quot;root&quot;: true,
      &quot;env&quot;: {
        &quot;node&quot;: true
      },
      &quot;extends&quot;: [
        &quot;plugin:vue/vue3-essential&quot;,
        &quot;eslint:recommended&quot;
      ],
      &quot;parserOptions&quot;: {
        &quot;parser&quot;: &quot;babel-eslint&quot;
      }
    },
    &quot;browserslist&quot;: [
      &quot;last 2 versions&quot;,
      &quot;safari &gt;= 7&quot;,
      &quot;ios_saf &gt;= 8&quot;,
      &quot;chrome &gt;= 52&quot;
    ]
  }
  </code></pre>
  <p>My babel.config.js:</p>
  <pre><code>module.exports = {
    presets: [
      ['@vue/babel-preset-app']
    ]
  }
  </code></pre>
  <p>I know that the error can be caused by not-transpiled dependencies, but I tried to transpile them in vue.config.js by <code>transpileDependencies</code> option. But doesn't work neither.</p>