[bojo]

Sorry to be that guy. I love nix, I want to read more about how people use nix.

The font presented under NixOS + Firefox is near unreadable on this website.

[mananaysiempre]

The font (family) is a variant of Computer Modern. Computer Modern is, unfortunately, an extreme example of the problem where a font designed to compensate for ink spread on physical paper looks overly thin on a computer screen. It is also, unfortunately, one of the very few free fonts with good support for mathematics.

[yakshaving_jgt]

Have you tried enabling Reader Mode in your browser?

[bmacho]

Does not work nice with code blocks. But here's how you can add Javascript Snippets to every webpage via Tampermonkey:

  // ==UserScript==
  // @name         JS Snippets
  // @match        *://*/*
  // @grant        GM_registerMenuCommand
  // ==/UserScript==
  
  GM_registerMenuCommand("Set font to default", () => {
      document.querySelectorAll("body *:not(pre *)").forEach(el => {
          el.style.fontFamily = "nonExistentFont";
      });
  });

you can run them by clicking the Tampermonkey icon and picking the action you want. You can add website dependent snippets by checking the location before you register the menu items, it's dynamic.