SDL 2.0.9 introduced a 32-pixel freedom for double clicks to register, which kind of breaks double clicking on Windows.
This uses the hint to revert that to 1.
The platform difference has been reported: https://bugzilla.libsdl.org/show_bug.cgi?id=5482
See https://hg.libsdl.org/SDL/rev/f081a5675f93 for the commit.