TYPO3 Core

Problem:
When using the 'install system extensions' function of the update wizard in install tool the resulting extlist in localconf.php will look like this: '...,llxmltranslate,_CACHEFILE,simulatestatic';

this is caused by function addExtToList() in class tx_coreupdates_installsysexts where all entries in $GLOBALS['TYPO3_LOADED_EXT'] are used as extension keys.

Solution:
remove the _CACHEFILE entry from $GLOBALS['TYPO3_LOADED_EXT'] before merging it with the list of new extensions.

(issue imported from #M11827)