I think I've fixed this in https://github.com/zopefoundation/Products.ZCatalog/commit/1b23ee66052a5ea9bc9c57a550917b4279d5fa4d. I wasn't related to multi-sorting, but removal of a `limit is None` protection for one of the search algorithms. This was a master only optimization.
I think I've fixed this in https:/ /github. com/zopefoundat ion/Products. ZCatalog/ commit/ 1b23ee66052a5ea 9bc9c57a550917b 4279d5fa4d. I wasn't related to multi-sorting, but removal of a `limit is None` protection for one of the search algorithms. This was a master only optimization.