I tried to make one, but the white wasn't mixing in properly.
Are you quite sure you you don’t mean RGBW/
Custom LED - RGWB.zip
Custom fixture personality attached. This was made by opening the built-in Generic LED-RGBW in the editor and swapping over the W and B.
I assume this is for an RGBW LED tape, a lot of tapes have the colors in a 'surprising' order.
