cdnjs doesn't work well with es6 modules or at least requires more manual labor. unpkg and jsdelivr work because they keep the structure defined in the package.json
https://twitter.com/centrisimo/status/1190213354213838855
https://twitter.com/vdanielpop/status/1190234073987518465
https://twitter.com/BaggaleyGeorge/status/119026004939189043...
https://github.com/mjackson/unpkg/issues/176
cdnjs doesn't work well with es6 modules or at least requires more manual labor. unpkg and jsdelivr work because they keep the structure defined in the package.json