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The HTMLSlotElement interface of the Shadow DOM API enables access to the name and assigned nodes of an HTML <slot> element.

DOMString: Can be used to get and set the slot's name.


Returns the sequence of elements assigned to this slot, or alternatively the slot's fallback content.


The following snippet is taken from our slotchange example (see it live also).

let slots = this.shadowRoot.querySelectorAll('slot');
slots[1].addEventListener('slotchange', function(e) {
  let nodes = slots[1].assignedNodes();
  console.log('Element in Slot "' + slots[1].name + '" changed to "' + nodes[0].outerHTML + '".');

Here we grab references to all the slots, then add a slotchange event listener to the 2nd slot in the template — which is the one that keeps having its contents changed in the example.

Every time the element inserted in the slot changes, we log a report to the console saying which slot has changed, and what the new node inside the slot is.


Specification Status Comment
HTML Living Standard
The definition of 'HTMLSlotElement' in that specification.
Living Standard  

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support53 No1 Yes2 No4010.1
name53 No1 Yes2 No4010.1
assignedNodes53 No1 Yes2 No4010.1
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support5353 No1 Yes24010.1 ?
name5353 No1 Yes24010.1 ?
assignedNodes5353 No1 Yes24010.1 ?

1. Under consideration

2. This feature is behind the dom.webcomponents.enabled preference (needs to be set to true) and the dom.webcomponents.shadowdom.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.

Document Tags and Contributors

 Last updated by: fscholz,