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function wp_is_mobile() {
	if ( isset( $_SERVER['HTTP_SEC_CH_UA_MOBILE'] ) ) {
		// This is the `Sec-CH-UA-Mobile` user agent client hint HTTP request header.
		// See <https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Sec-CH-UA-Mobile>.
		$is_mobile = ( '?1' === $_SERVER['HTTP_SEC_CH_UA_MOBILE'] );
	} elseif ( empty( $_SERVER['HTTP_USER_AGENT'] ) ) {
		$is_mobile = false;
	} elseif ( str_contains( $_SERVER['HTTP_USER_AGENT'], 'Mobile' ) // Many mobile devices (all iPhone, iPad, etc.)
		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'Android' )
		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'Silk/' )
		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'Kindle' )
		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'BlackBerry' )
		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'Opera Mini' )
		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'Opera Mobi' ) ) {
			$is_mobile = true;
	} else {
		$is_mobile = false;
	}

	/**
	 * Filters whether the request should be treated as coming from a mobile device or not.
	 *
	 * @since 4.9.0
	 *
	 * @param bool $is_mobile Whether the request is from a mobile device or not.
	 */
	return apply_filters( 'wp_is_mobile', $is_mobile );
}