Desmos Dark Mode

desmos.dark.user.js

// ==UserScript==
// @name         Desmos Dark Mode
// @namespace    https://alexapps99.github.io/
// @version      0.3.0
// @description  Improved dark mode colors for Desmos, with images and colors displayed correctly. Note: To disable dark mode being on by default, comment out line 15.
// @author       AlexApps99
// @source       https://gist.github.com/AlexApps99/519c7bcef683244bd944497ce96940a2
// @downloadURL  https://gist.githubusercontent.com/AlexApps99/519c7bcef683244bd944497ce96940a2/raw/desmos.dark.user.js
// @match        http://www.desmos.com/calculator*
// @match        https://www.desmos.com/calculator*
// ==/UserScript==

setTimeout((function() {
    "use strict";
    // Comment out the below line to disable Dark Mode being on by default
    let DARK_MODE_ON_BY_DEFAULT = true;

    if (!window._ditc_old && !window._ditc_new) {
        // Add styles
        let s = document.createElement("style");
        document.head.appendChild(s);
        // For the entire screen
        s.sheet.insertRule(".dcg-calculator-api-container > .dcg-container.dcg-inverted-colors { filter: invert(100%) hue-rotate(180deg) !important; }");
        // For the little icon circle
        s.sheet.insertRule(".dcg-calculator-api-container > .dcg-container.dcg-inverted-colors .dcg-has-background-image > .dcg-background-image { filter: hue-rotate(-180deg) invert(100%) !important; }");

        // Patch image drawing code
        let ditc = require("graphing/draw-image-to-ctx");
        window._ditc_old = ditc.drawImageToCtx;
        window._ditc_new = function(e, r, i) {
            let darkMode = !!document.querySelector(".dcg-calculator-api-container > .dcg-container.dcg-inverted-colors");
            if (darkMode) {
                r.filter = "hue-rotate(-180deg) invert(100%)";
            }
            let ret = window._ditc_old.apply(this, arguments);
            if (darkMode) {
                r.filter = "none";
            }
            return ret;
        }
        ditc.drawImageToCtx = window._ditc_new;
    }
    if (typeof DARK_MODE_ON_BY_DEFAULT !== "undefined" && DARK_MODE_ON_BY_DEFAULT) {
        Calc.updateSettings({
            invertedColors: true
        });
    }
    console.log("Desmos Dark Mode applied");
}), 1000);

it does not work

The last time I updated this was 2021, so I'm not surprised!
Hopefully there are some other userscripts around that are still actively maintained.