The plan is to use Microsoft Visual Studio C++ compiler (msvc) to compile the final official v6 release, so the upper link is going towards it. If there are problems in the msvc nightly builds you can always go back to the msys2 builds.
… maybe I should mention that this particular version mentioned here is problematic as it crashes when opening Footprint editor. There’s a recent release (dated 28.03) that fixes the problem.