When searching in LO online (built-in) help on OSX, the search returns hits in the left pane, but clicking on one of them does not open that help page in the right pane, just pure white is displayed.
Created attachment 121042 [details] screenshot with missing text for index items in helper package
Can confirm this for 5.1.0.0 beta2 Winx64 with installed HelperPackage (Germ), no text is displayed by clicking on an index list item or hitting the show button "Anzeige" see attached screenshot
*** This bug has been marked as a duplicate of bug 96042 ***