How to use the medium.js.partialMode function in medium

initMedium() {
      // initialising editor. see http://jakiestfu.github.io/Medium.js/docs/
      this.medium = new Medium({
        element: this.mediumMount(),

        modifier: "auto",
        placeholder:
          "What? - Short title shown in lists <br> Longer description. You can use #tags",
        autoHR: false, //if true, inserts <hr> after two empty lines
        mode: Medium.partialMode, // allows newlines, no styling
        attributes: {
          //remove: ['style', 'class'] //TODO does this remove the ng-class?
          remove: ["style"], //TODO does this remove the ng-class?
        },
        beforeInsertHtml: function() {
          //this = Medium.Html (!)

          // Replace `<br>`s with the `<p>`s we use for line-breaking, to allow
          // multi-line pasting. This assumes that pasting happens inside
          // a `</p><p>` element and will horribly fail otherwise.
          // The trimming happens, as leading whitespaces are removed in other
          // lines as well during pasting.
          const originalHtml = this.html;
          const sanitizedHtml = originalHtml.trim().replace(/<br>/g, "</p><p>");
          this.html = sanitizedHtml;
</p>