Hi all, does anyone have any ideas on how to repair/fix the weird mottling on the rear windows on the Octavia Estate?

It looks like it was most likely sun damage after a product was applied perhaps.

I presume the only remedial action is a bit of a cutting compound to even the surface? I've tried a few products for rubber and plastic care but apart from hiding it in a greasy film it never fully resolves it.

Cheers!

Edited 18 June18 Jun by Plantman

Honestly? A replacement is likely the only option. Rubber is very finicky and difficult to work with - you have to be very careful. It doesn't look like UV damage to me.. I think something has dried on there, or has been too strong (TFR is a common cause of this) and burnt into the rubber.

You can't polish rubber. If it were me, I would try some IPA on it, followed by some trim restorer, and hope for the best. A dedicated rubber cleaner, like that for tyres, won't work in this case. Similarly, no amount of cleaning (with water spot remover, panel wipe, etc) will get that off.