For having multiple specs in swagger-ui

index.html

      <script>
      // ... 
      var selectedUrl = "One";

      var spec = {
        "One": "/One.json",
        "Two": "/Two.json"
      }

      function updateMultipleSpecs() {
        var sel = $('#input_baseUrl');
        sel.html("");
        $.each(spec,function(key,val){
          var opt = $('<option>')
            .prop('value', val)
            .prop('selected', selectedUrl === val)
            .html(key);
          sel.append(opt);
        });
      }

      $('#input_baseUrl').change(function() {
        var url = $(this).val();
        window.swaggerUi.updateSwaggerUi({
          url: url
        });
        selectedUrl = url;
        updateMultipleSpecs();
      });

      updateMultipleSpecs();
      // ...
      </script>
      
      <!-- ... -->
      
      <!-- replace existing input_baseUrl with a select -->
      <div class="input">
        <select id="input_baseUrl" name="baseUrl"></select>
      </div>
      <!-- ... -->

Just a note that latest swagger ui supports a "urls" param which looks a little like
[ { "name": "My First API", "url": $url_of_swagger_file }, ... ]
Which will change the text-entry box at top to a drop-down of "name" values and auto-update the displayed swagger when a new one is selected.
See swagger-api/swagger-ui@2e40f59

Is the value 'selectedUrl' the correct way to setup the default selection ? in some other code snippet, I found that 'urls.primaryName' was used.

When I try this I get an error on page load:

Uncaught TypeError: consumes.filter is not a function
    at C.n.contains (StatusCodeView.js:32)
    at C.n.render (StatusCodeView.js:32)
    at C.n.addParameter (StatusCodeView.js:32)
    at C.n.render (StatusCodeView.js:32)
    at C.n.addOperation (StatusCodeView.js:32)
    at C.n.render (StatusCodeView.js:32)
    at C.n.addResource (StatusCodeView.js:32)
    at C.n.render (StatusCodeView.js:32)
    at C.n.render (StatusCodeView.js:32)
    at module.exports.options.success (StatusCodeView.js:32)