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function is not described

convert_invalid_entities() WP 4.3.0

Converts invalid Unicode references range to valid range.

No Hooks.

Return

String. Converted string.

Usage

convert_invalid_entities( $content );
$content(string) (required)
String with entities that need converting.

Code of convert invalid entities: wp-includes/formatting.php VER 5.1.1

<?php
function convert_invalid_entities( $content ) {
	$wp_htmltranswinuni = array(
		'&#128;' => '&#8364;', // the Euro sign
		'&#129;' => '',
		'&#130;' => '&#8218;', // these are Windows CP1252 specific characters
		'&#131;' => '&#402;',  // they would look weird on non-Windows browsers
		'&#132;' => '&#8222;',
		'&#133;' => '&#8230;',
		'&#134;' => '&#8224;',
		'&#135;' => '&#8225;',
		'&#136;' => '&#710;',
		'&#137;' => '&#8240;',
		'&#138;' => '&#352;',
		'&#139;' => '&#8249;',
		'&#140;' => '&#338;',
		'&#141;' => '',
		'&#142;' => '&#381;',
		'&#143;' => '',
		'&#144;' => '',
		'&#145;' => '&#8216;',
		'&#146;' => '&#8217;',
		'&#147;' => '&#8220;',
		'&#148;' => '&#8221;',
		'&#149;' => '&#8226;',
		'&#150;' => '&#8211;',
		'&#151;' => '&#8212;',
		'&#152;' => '&#732;',
		'&#153;' => '&#8482;',
		'&#154;' => '&#353;',
		'&#155;' => '&#8250;',
		'&#156;' => '&#339;',
		'&#157;' => '',
		'&#158;' => '&#382;',
		'&#159;' => '&#376;',
	);

	if ( strpos( $content, '&#1' ) !== false ) {
		$content = strtr( $content, $wp_htmltranswinuni );
	}

	return $content;
}