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function is not described

wp_mediaelement_fallback() WP 3.6.0

Provides a No-JS Flash fallback as a last resort for audio / video.

Hooks in function
Return

String. Fallback HTML.

Usage

wp_mediaelement_fallback( $url );
$url(string) (required)
The media element URL.

Code of wp mediaelement fallback: wp-includes/media.php WP 5.2.2

<?php
function wp_mediaelement_fallback( $url ) {
	/**
	 * Filters the Mediaelement fallback output for no-JS.
	 *
	 * @since 3.6.0
	 *
	 * @param string $output Fallback output for no-JS.
	 * @param string $url    Media file URL.
	 */
	return apply_filters( 'wp_mediaelement_fallback', sprintf( '<a href="%1$s">%1$s</a>', esc_url( $url ) ), $url );
}