I’m going to refer you to Wikipedia’s newspaper The Signpost, but if there’s jargon in there that makes no sense, I can clarify. The TL;DR is that the skin Vector (2022) (an update from Vector (2010)) made the interface more flexible to customization, logged-out users could now have preferences, and Wikipedia’s design was all over the place after 20 years of largely decentralized development.
Why did it take Wikipedia so long to add dark mode?
I’m going to refer you to Wikipedia’s newspaper The Signpost, but if there’s jargon in there that makes no sense, I can clarify. The TL;DR is that the skin Vector (2022) (an update from Vector (2010)) made the interface more flexible to customization, logged-out users could now have preferences, and Wikipedia’s design was all over the place after 20 years of largely decentralized development.