The Greatest Hits page (like the one on Stack Overflow) displays 1000 items with a page size of 50, but has 21 pages:
As a result, the last page is always empty and should just not be included.
answer-loader.js attempts to call
StackExchange.vote_closingAndFlagging.init() which is undefined for them. I'm not entirely sure what that script does off-hand, but might be remnants of the functionality removed in the fix for this issue?