How do I init range slider in popup

I have a popup where a user needs to select what floor of a building they’re on and I’m trying to use a range slider but, apparently, the range slider is not being initialized.

Most of the slider layout gets drawn but no button gets displayed so, based on searches here it looks like the slider is not being initialized. I see no method for initializing the slider other than create and since it’s already created that doesn’t quite make sense to me. Is there no init function that will use the existing slider and parameters? If not, what’s the shortest amount of code that will “create” the slider using all the exiting settings?

The range slider html looks like this:

<div class="list simple-list">
    <li class="item-row">
      <div class="item-cell width-auto flex-shrink-0">
        <span class="fa fas-arrow-down"></span>
      <div class="item-cell item-cell-shrink-3">
        <!-- Range slider with all the parameters passed via data- attributes -->
        <div class="range-slider range-slider-init color-orange" data-label="true">
          <input id="rangeFloor" type="range" min="0" max="100" step="1" value="1" data-label="true">
      <div class="item-cell width-auto flex-shrink-0">
        <span class="fa fas-arrow-up"></span>

And, FWIW, this did nothing:

var range = app.range.create({inputEl:	'#rangeFloor',
                    step: 1,
                    label: true,
                    min: 0,
                    max: 100,
                    value: userInfo.getFloor(),
                    draggableBar: true,
                    vertical: false});

It is app.range.create. And you didn’t pass the most important parameter el

Based on the html provided what is el?