Excel also has a deliberate bug where it thinks 1900 is a leap year because they wanted compatibility with Lotus 123, where the bug was actually a bug! [0] [0] [this video]
can't speak about the very recent updates, but windows have been consistent and adamant on keeping the backward compatibility. they still use reserved file names for io devices so that 30+ year old printers can still work, and you can still open a 2000s doc file in office 365. (I'm looking at you Apple, who made many of the 32 bit apps I loved useless) relevant video: [this video] (Tom Scott: Why you can't use CON as filename in windows)
It's wild to me some of the things I never knew, even though I've been using Windows or DOS for probably 35 years. For example, I recently learned you can't name a file CON. Try it. Somehow over all those decades, I've never tried to do this until Tom Scott made a video about it: [this video]
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