Or maybe don't have sketches which make fun of people of colour, disabled, or any other minority? Blackface is rooted in caricature and racism. Just like drag is offensive to women as it depicts us all as overly made up tarts. Some of the comments on this thread are shocking, and to think social media is full of people saying there's no racism in the UK.So going forward what will happen? your going to have to hire a black person to do the black sketch.
Why hasn't it been brought up before? Well maybe because black voices and the voices of the disabled are always ignored. No one listens. Even now blm is drowned out by mainly white people removing statues of racists because they have more of powerful voice and footprint. Of course, it's people of colour who are being attacked for the removal of statues.
Seriously, if any of you don't have an issue with blackface then please understand that you are racist. Go away and reflect. Read up on the history of it, why it's offensive, instead posting on a forum when you can easily Google the answers to inane questions like 'why are people offended though hun?'.