Fixes the __getitem__ error when overlaying VectorFields in Stacks
Fixes the __getitem__ error when overlaying VectorFields in Stacks

vascotenner/holoviews,mjabri/holoviews,ioam/holoviews,mjabri/holoviews,vascotenner/holoviews,ioam/holoviews,vascotenner/holoviews,basnijholt/holoviews,basnijholt/holoviews,mjabri/holoviews,ioam/holoviews,basnijholt/holoviews