Yes, for a few years the Brexit Party was the I'mNotRacistBut Party. It looks like they've now been rumbled (hence becoming unelectable), so they're rebranding as Reform, which might last for another few years.

The previous I'mNotRacistBut Party was UKIP (featuring Stephen Yaxley-Lennon as advisor for racially-charged issues, and denounced as racist 24 years ago by its own founder)

Before that the BNP was scoring a few percent in general elections.

And around and around it goes, all the way back to Mosley's blackshirts.