Considering to join a lemmy instance not the least because it says “you can also blog on lemmy” (https://join-lemmy.org/docs/users/06-other-features.html?highlight=blog#lemmy-as-a-blog) I have one question though:
Can I have MathJax or KaTeX to do formulas?
As already mentioned, it’s not supported by default.
You can enable it by adding a plugin like markdown-it-mathjax3, so you’d either need to modify your own instance or find one that already supports it.
I’ve added a few such features to my own server, since I’m using it partly for blogging.
https://lm.korako.me/post/8470\ https://github.com/karasugawasu/lemmy-ui/commit/0482fda3cb9d0deae80d5c52a4736fad6ccb12bf