Are spiders pooing on my windowsills, having presumably finished wiping their Willies on my washing?

[StealthPolarBear]

Today is window cleaning day, dh the outsides, me the insides. On the bottom of the window frames and sometimes on the sills there are some brown blotches, which are difficult to get off even with jif. Is this spider poo?
If not then where do spiders poo?
And what do lady spiders wipe on our clean washing?

Definitely spider poo! Dirty little leggy bastards.

Spider vagina?

Yuck. They should carry tiny poo bags. So antisocial

I missed all the spider willy wiping stuff, and still wonder what it's all about. Is it their version on wiping it on the curtains after doing the dirty spidery deed?

They do that thing dogs do when they drag their bums across the flood

Floor

Ipswich are you thinking of dogs? :o