Today's image from "Wikimedia Picture of the Day" contains nudity . I discovered that because I was browsing some NSFW content in my web browser and I head somebody coming behind me, so I hit the shortcut to minimize all windows and BAM! Titties all over the place on my Desktop as well.
STEPS TO REPRODUCE
1. Change the Wallpaper provider to "Wikimedia Picture of the Day"
2. Wait for tits.
Still tits, but maybe a big fat warning should be added explaining the consequences of using such image providers?
KDE Plasma Version: 5.13.5
KDE Frameworks Version: 5.50.0
Qt Version: 5.11.2
If it was not clear, I'm joking about the whole situation, I wasn't bothered by it at all. But I see how troublesome it can be. Wikimedia already has a template for tagging submitted NSFW images  (and I don't know if KDE already checks for that), but either way, this particular image wasn't even tagged. So whilst there's a solution for tagging NSFW images, sometimes people won't use it. A warning should be enough, IMHO. Thanks!
From what I know we do not check for the Nsfw tag/category in wikimedia potd provider.
Adding a text label warning of that could be trivially added added. 
We could also filter out NSFW images by checking for that tag. I think the desktop is probably a semi-dangerous place for NSFW images to randomly appear without warning, so that's reasonable IMO. :)
A possibly relevant merge request was started @ https://invent.kde.org/plasma/kdeplasma-addons/-/merge_requests/180
Git commit 4c5beee31c6d0fcf8388616c70104b45a6a95b6c by Fushan Wen.
Committed on 13/01/2023 at 15:44.
Pushed by fusionfuture into branch 'master'.
wallpapers/potd: show prompt when images from external wallpaper providers might have NSFW content
M +20 -10 wallpapers/potd/package/contents/ui/config.qml
M +9 -0 wallpapers/potd/plugins/potdprovidermodel.cpp
M +2 -0 wallpapers/potd/plugins/potdprovidermodel.h
M +2 -1 wallpapers/potd/plugins/providers/wcpotdprovider.json