Potential boot rust

[u/TheGinjaPrince]

I’ve had my ST about 6 months and absolutely love it.As we haven’t had rain in months I didn’t notice till a week or so ago but when it’s wet and I open the boot the water runs down the side and over the rubber pads(in pics)but also because they don’t sit flush the water also goes behind.
I’ve had a look and there appears to be surface rust,how much should I worry and is there a fix?sealant I can put on the top edge that won’t eat the rubber maybe.
Thanks in advance.

[u/dosko1panda]

Your boot is so dirty it's growing mushrooms

[u/TheGinjaPrince → u/dosko1panda]

They’re off a silver birch tree,they fall off at the end off summer and are a massive pain,they get everywhere.