PhpStorm adding script to my GET responses [closed]

I’m responding to a GET request with JSON data (Content-Type
application/json; charset=utf-8), but it keeps tacking on this random script to every response and I cannot get rid of it no matter what I do:

37 requests
720.83 kB / 707.49 kB transferred
Finish: 602 ms
DOMContentLoaded: 214 ms
load: 476 ms
SyntaxError: JSON.parse: unexpected non-whitespace character after JSON data at line 1 column 503 of the JSON data

{"expected_data":"values"}<script>
(function() {
  var ws = new WebSocket('ws://' + window.location.host + 
             '/jb-server-page?reloadMode=RELOAD_ON_SAVE&'+
             'referrer=' + encodeURIComponent(window.location.pathname));
  ws.onmessage = function (msg) {
      if (msg.data === 'reload') {
          window.location.reload();
      }
      if (msg.data.startsWith('update-css ')) {
          var messageId = msg.data.substring(11);
          var links = document.getElementsByTagName('link');
          for (var i = 0; i < links.length; i++) {
              var link = links[i];
              if (link.rel !== 'stylesheet') continue;
              var clonedLink = link.cloneNode(true);
              var newHref = link.href.replace(/(&|?)jbUpdateLinksId=d+/, "$1jbUpdateLinksId=" + messageId);
              if (newHref !== link.href) {
                clonedLink.href = newHref;
              }
              else {
                var indexOfQuest = newHref.indexOf('?');
                if (indexOfQuest >= 0) {
                  // to support ?foo#hash 
                  clonedLink.href = newHref.substring(0, indexOfQuest + 1) + 'jbUpdateLinksId=' + messageId + '&' + 
                                    newHref.substring(indexOfQuest + 1);
                }
                else {
                  clonedLink.href += '?' + 'jbUpdateLinksId=' + messageId;
                }
              }
              link.replaceWith(clonedLink);
          }
      }
  };
})();
</script>

Does anyone know where this script is coming from and how I can disable it? I’ve also tried disabling the debugger in both my browser and in PhpStorm.

I’ve searched high and low and I know it has something to do with “live edit”, but I cannot find any options to enable/disable it no matter where I look.