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function is not described

wp_kses_bad_protocol_once() WP 1.0.0

Sanitizes content from bad protocols and other characters.

This function searches for URL protocols at the beginning of the string, while handling whitespace and HTML entities.

No Hooks.

Return

String. Sanitized content.

Usage

wp_kses_bad_protocol_once( $string, $allowed_protocols, $count );
$string(string) (required)
Content to check for bad protocols.
$allowed_protocols(string[]) (required)
Array of allowed URL protocols.

Code of wp kses bad protocol once: wp-includes/kses.php WP 5.2.2

<?php
function wp_kses_bad_protocol_once( $string, $allowed_protocols, $count = 1 ) {
	$string2 = preg_split( '/:|&#0*58;|&#x0*3a;/i', $string, 2 );
	if ( isset( $string2[1] ) && ! preg_match( '%/\?%', $string2[0] ) ) {
		$string   = trim( $string2[1] );
		$protocol = wp_kses_bad_protocol_once2( $string2[0], $allowed_protocols );
		if ( 'feed:' == $protocol ) {
			if ( $count > 2 ) {
				return '';
			}
			$string = wp_kses_bad_protocol_once( $string, $allowed_protocols, ++$count );
			if ( empty( $string ) ) {
				return $string;
			}
		}
		$string = $protocol . $string;
	}

	return $string;
}