TYPO3 Core

If I load an extension into the extension manager view I get quite a lot
messages like this:

Warning: preg_match(): Unknown modifier 'C' in H:\webroot\interports\code\php\typo3\mod\tools\em\index.php on line 2708

which results in a lot error messages like this

Couldn't find the include_once statement for XCLASS!

Problem seems to be that the above mentioned preg_match has no delimiter set, I set mine to "$" and quoted $cmpF just to ensure that it won't contain unescaped "$". The whole line 2708 now looks like this:

if (preg_match('$_once[[:space:]]*\(\$TYPO3_CONF_VARS\[TYPO3_MODE\]\[[\'"]XCLASS[\'"]\]\[[\'"]'.preg_quote($cmpF).'[\'"]\]\);$', $XclassParts¹)) {

(issue imported from #M1375)