_wp_render_title_tag() │ WP 4.1.0

Displays title tag with content.

Internal function — this function is designed to be used by the kernel itself. It is not recommended to use this function in your code.

No Hooks.

Returns

null. Nothing (null).

Usage

_wp_render_title_tag();

Changelog

Since 4.1.0 Introduced.
Since 4.4.0 Improved title output replaced wp_title().

_wp_render_title_tag() code WP 7.0

wp-includes/general-template.php 
function _wp_render_title_tag() {
	if ( ! current_theme_supports( 'title-tag' ) ) {
		return;
	}

	echo '<title>' . wp_get_document_title() . '</title>' . "\n";
}