Scummy washing machine door - how to get rid of black stuff on the inside rubber bit?

[notnowbernard]

Is this possible?

Or is it beyond saving?

Have tried to scrub it off but it's pretty thick

Explanation here

Thanks for that

Might be forking out for a replacement door seal...

My door is worse than the pictured example, which they described as an "extreme case"

I had that. I've now gone back to using powder rather than liquid and do I biological hot wash with an empty machine, cleaned it all by itself!