is there a reason we don't xlog index free space?

I knew that XLogRecordPageWithFreeSpace() is only called by heapam.c,
but I figured indexes had their own logic to xlog free space. While
investigating something else I found that brin indexes, at least, on
the secondary have no FSMs. Is this deliberate?

-- 
John Naylor                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services