Oh sorry, yes I have a browser extension that always adds that parameter to any wikipedia page. I usually strip it when posting a link, but I forgot (and since it's a long link, it doesn't display in its entirety so I didn't catch it).

I just discovered that feature due to your mistake, so thank you!

For similarly newly enlightened people it's a feature of MediaWiki (which Wikipedia runs on) and there are five (plus two) themes selectable with ?useskin= values:

- timeless (as seen above): https://en.wikipedia.org/wiki/Wikipedia:Skin?useskin=timeles...

- monobook (default 2004-2009): https://en.wikipedia.org/wiki/Wikipedia:Skin?useskin=monoboo...

- vector (default 2010-2021): https://en.wikipedia.org/wiki/Wikipedia:Skin?useskin=vector

- vector-2022 (desktop default 2022-): https://en.wikipedia.org/wiki/Wikipedia:Skin?useskin=vector-...

- minerva (mobile default): https://en.wikipedia.org/wiki/Wikipedia:Skin?useskin=minerva

- modern (delightedly dated, deprecated): https://en.wikipedia.org/wiki/Wikipedia:Skin?useskin=modern

- cologneblue (also ancient and anti-favored): https://en.wikipedia.org/wiki/Wikipedia:Skin?useskin=cologne...

You can also choose a preferred skin when you log in and go to Preferences → Appearance.

That makes sense! I can see why you would prefer that skin. Out of curiosity, why use a plugin and not Wikipedia's appearance preferences[1]?

1: https://en.wikipedia.org/wiki/Special:Preferences#mw-prefsec...

IIRC that requires having an account and being logged in, or maybe it just required a persistent cookie to remember the preference. Either way, my browser still aggressively clears cookies on exit so this solution was more permanent for me than the official solution.