I have found the error messages of the function
function Werbung(&$parser, &$text) {
$text = preg_replace_callback ('//', "getPOIs", $text);
#echo $text;
#echo "<br><brblblb lblbllbd lbalbab.<br><br>";
return(true);
}
which I set in the LocalSettings.php
Werbung ( $parser, $text );
(instead of the old Hook #$wgHooks['ParserBeforeStrip'][]='Werbung';)
Deprecated: preg_replace_callback(): Passing null to parameter #3 ($subject) of type array|string is deprecated in /usr/www/users/abc/archiv24/extensions/Werbung/Werbung.php on line 49
Notice: Headers already sent, should send headers earlier than require [Called from MediaWiki\Request\HeaderCallback::warnIfHeadersSent in /usr/www/users/veikkoc/archiv24/includes/Request/HeaderCallback.php at line 94] in /usr/www/users/abc/archiv24/includes/debug/MWDebug.php on line 492
Warning: session_name(): Session name cannot be changed after headers have already been sent in /usr/www/users/abc/archiv24/includes/Setup.php on line 472