This example uses OpenLayers v10.9.0. The latest is v.
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#### Mouse Position

mouse-position 2 openstreetmap 22

#####

Projection
Precision

Example of a mouse position control, outside the map.

Example of a mouse position control, outside the map.

##### main.js

    import Map from 'ol/Map.js';
    import View from 'ol/View.js';
    import MousePosition from 'ol/control/MousePosition.js';
    import {defaults as defaultControls} from 'ol/control/defaults.js';
    import {createStringXY} from 'ol/coordinate.js';
    import TileLayer from 'ol/layer/Tile.js';
    import OSM from 'ol/source/OSM.js';

    const mousePositionControl = new MousePosition({
      coordinateFormat: createStringXY(4),
      projection: 'EPSG:4326',
      // comment the following two lines to have the mouse position
      // be placed within the map.
      className: 'custom-mouse-position',
      target: document.getElementById('mouse-position'),
    });

    const map = new Map({
      controls: defaultControls().extend([mousePositionControl]),
      layers: [
        new TileLayer({
          source: new OSM(),
        }),
      ],
      target: 'map',
      view: new View({
        center: [0, 0],
        zoom: 2,
      }),
    });

    const projectionSelect = document.getElementById('projection');
    projectionSelect.addEventListener('change', function (event) {
      mousePositionControl.setProjection(event.target.value);
    });

    const precisionInput = document.getElementById('precision');
    precisionInput.addEventListener('change', function (event) {
      const format = createStringXY(event.target.valueAsNumber);
      mousePositionControl.setCoordinateFormat(format);
    });

##### index.html

    <!DOCTYPE html>
    <html lang="en">
      <head>
        <meta charset="UTF-8">
        <title>Mouse Position</title>
        <link rel="stylesheet" href="node_modules/ol/ol.css">
        <style>
          .map {
            width: 100%;
            height: 400px;
          }
        </style>
      </head>
      <body>
        <div id="map" class="map"></div>
        <div id="mouse-position"></div>
        <form>
          <label for="projection">Projection </label>
          <select id="projection">
            <option value="EPSG:4326">EPSG:4326</option>
            <option value="EPSG:3857">EPSG:3857</option>
          </select>
          <label for="precision">Precision</label>
          <input id="precision" type="number" min="0" max="12" value="4"/>
        </form>

        <script type="module" src="main.js"></script>
      </body>
    </html>

##### package.json

    {
      "name": "mouse-position",
      "dependencies": {
        "ol": "10.9.0"
      },
      "devDependencies": {
        "vite": "^3.2.3"
      },
      "scripts": {
        "start": "vite",
        "build": "vite build"
      }
    }