Fixes the 3D buildings failing to load (the MapLibre "..._classRegistryKey" error) over any map tile that contains a standalone Polygon building, e.g. a freshly-mapped shed. The buildings source rebuilds such features with a clean prototype instead of choking on the null-prototype properties returned by the vector-tile decoder, so the buildings render everywhere again.
Prerelease, enable beta versions in HACS to install.