In the past 8 hours, on the Dutch Wikipedia the sandbox link in one's personal bar to someone's sandbox (in Dutch: "Kladblok") in the user namespace has changed. Before the link linked to User:Xyz/Kladblok (with capital K). Now it links to User:Xyz/kladblok with lower case k. As these pages are capital sensitive, all links have become red and people experience that as their sandbox being gone.

Can this be fixed that again the capital K is used as first character after the /

Thanks!