join_pages is not configurable
In indexed_search documentation, section
"Handling extendToSubpages - or not":
the join_pages parameter is mentioned. But this is a class variable which cannot be configured. Setting this to 1 is needed on sites with a huge page-tree is needed, else the indexed_search query is useless (>30secs per request).
So this feature request is to make this option configurable via TypoScript.
(issue imported from #M5791)