Document: mozSetImageElement() method

Non-standard: This feature is not standardized. We do not recommend using non-standard features in production, as they have limited browser support, and may change or be removed. However, they can be a suitable alternative in specific cases where no standard option exists.

The Document.mozSetImageElement() method changes the element being used as the CSS background for a background with a given background element ID.

Syntax

js
mozSetImageElement(imageElementId, imageElement)

Parameters

imageElementId

A string indicating the name of an element that has been specified as a background image using the -moz-element CSS function.

imageElement

The new element to use as the background corresponding to that image element string. Specify null to remove the background element.

Return value

None (undefined).

Examples

This example changes the background of a <div> block each time the block is clicked by the user.

View this example live.

css
#my-box {
  background-image: -moz-element(#canvas-bg);
  text-align: center;
  width: 400px;
  height: 400px;
  cursor: pointer;
}

The CSS defined above is used by our <div> to use an element with the id "canvas-bg" as its background.

js
let c = 0x00;
function clicked() {
  const canvas = document.createElement("canvas");
  canvas.setAttribute("width", 100);
  canvas.setAttribute("height", 100);

  const ctx = canvas.getContext("2d");
  ctx.fillStyle = `#${c.toString(16)}0000`;
  ctx.fillRect(25, 25, 75, 75);

  c += 0x11;
  if (c > 0xff) {
    c = 0x00;
  }

  document.mozSetImageElement("canvas-bg", canvas);
}

The code here is called each time the user clicks the <div> element. It creates a new <canvas> with the width and height set to 100 pixels, then draws into it a 50 by 50 pixel square. Each time the function is called, the square is a different color (its red component is increased each time), so each time the user clicks the element, the background is filled with a brighter and brighter pattern of red tiles.

Once the canvas is drawn, document.mozSetImageElement() is called to set the background for any CSS using the ID "canvas-bg" as its background element ID to be our new canvas.

Specifications

Not part of any specification.

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
mozSetImageElement
Non-standard
Chrome – No support
Chrome
footnote No support
Edge – No support
Edge
footnote No support
Firefox – Full support
Firefox 4 (Release date: 2011-03-22)
footnote Full support
Opera – No support
Opera
footnote No support
Safari – No support
Safari
footnote No support
Chrome Android – No support
Chrome Android
footnote No support
Firefox for Android – Full support
Firefox for Android 4 (Release date: 2011-03-29)
footnote Full support
Opera Android – No support
Opera Android
footnote No support
Safari on iOS – No support
Safari on iOS
footnote No support
Samsung Internet – No support
Samsung Internet
footnote No support
WebView Android – No support
WebView Android
footnote No support
WebView on iOS – No support
WebView on iOS
footnote No support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
No support
No support
Non-standard. Check cross-browser support before using.

See also