Document.firstElementChild

The Document.firstElementChild read-only property returns the document's first child Element, or null if there are no child elements.

For HTML documents, this is usually the only child, the root <html> element.

See Element.firstElementChild for the first child element of specific elements within a document.

Syntax

// Getter
element = document.firstElementChild;

// No setter; read-only property

document.firstElementChild;
// returns the root <html> element, the only child of the document

Specification
DOM Standard (DOM) # ref-for-dom-parentnode-firstelementchild①

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`firstElementChild`	29	17	25	No	16	9	≤37	29	25	16	9	2.0