[Typo3] Extension "Who is online" seems to be broken with 3.8

[dieter]

I have the same experience... 
the problem is that the missing file is in the directory above! 
it s not in  ./typo3conf/ext/gsi_whoisonline/pi1/locallang.php
but it s in ./typo3conf/ext/gsi_whoisonline/locallang.php

but in my case I can't seem to set my permissions on my host so that I can move
the file to the parent dir to see if that helps...