Some came over from the US but traditionally, not. Not even memorial days are that common. Just the big ones and the Cristian holidays.

No they made people up that got mad. It’s just sympathy bait. It’s most likely an ad to fake interest in a hopeless project

Yes. Markup-Languages are a subset of Programming-Languages. Turing completness doesn’t matter as things like magic the gathering and habbo hotel are Turing complete