Added LaTeX support to BetterGPT

BetterGPT LaTeX.user.js

// ==UserScript==
// @name         BetterGPT LaTeX
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Added LaTeX support to BetterGPT
// @author       rjf89
// @match        https://animalnots.github.io/BetterChatGPT-PLUS/
// @grant        none
// ==/UserScript==

// --- 1. Configure MathJax ---
// Set up configuration *before* loading the MathJax script.
// Use the window.MathJax object for configuration.
window.MathJax = {
    extensions: ["tex2jax.js"],
    tex2jax: {
        inlineMath: [
            ['[;',';]'],
            ['$$','$$']
        ],
        displayMath: [
            ['[(;',';)]'],
            ['[',']']
        ],
        skipTags: ["script", "noscript", "style", "textarea", "pre", "code"],
        processEscapes: true
    },
    jax: ["input/TeX", "output/HTML-CSS"],
    messageStyle: "none", // Optional: Hides the "Processing Math..." messages
    "HTML-CSS": {
        availableFonts: ["TeX"], // Use TeX fonts for better consistency
        linebreaks: { automatic: true } // Enable automatic line breaking
    },
    // --- Hook to run code after MathJax is fully loaded and ready ---
    AuthorInit: function () {
        console.log("MathJax is initialized and ready.");
        // --- 3. Setup MutationObserver after MathJax is ready ---
        setupMathJaxMutationObserver();
    }
};

// --- Function to Set Up the Mutation Observer ---
function setupMathJaxMutationObserver() {
    // Check if MathJax Hub is available
    if (!window.MathJax || !window.MathJax.Hub) {
        console.warn("MathJax Hub not ready yet for MutationObserver setup. Retrying in 200ms.");
        // Retry shortly, MathJax might still be initializing
        setTimeout(setupMathJaxMutationObserver, 200);
        return;
    }

    const targetNode = document.body; // Observe the entire body, or a more specific container element if possible
    const observerConfig = {
        childList: true, // Watch for direct children changes (nodes added/removed)
        subtree: true    // Watch descendants as well
    };

    const observerCallback = function(mutationsList, observer) {
        // Use a flag to avoid queueing multiple times for a single batch of mutations
        let nodesAdded = false;
        for (const mutation of mutationsList) {
            if (mutation.type === 'childList' && mutation.addedNodes.length > 0) {
                nodesAdded = true;
            }
        }

        // If any nodes were added in this batch of mutations, tell MathJax to typeset
        if (nodesAdded) {
            console.log("Detected added content, queueing MathJax Typeset.");
            // --- 4. Tell MathJax to process the content ---
            // Queue a command to typeset the *entire targetNode*.
            // While typesetting only mutation.addedNodes is more granular,
            // typesetting the container (targetNode) is often simpler and more robust,
            // especially if math spans across multiple added elements.
            // Adjust targetNode if you know changes only happen within a specific div.
            MathJax.Hub.Queue(["Typeset", MathJax.Hub, targetNode]);
        }
    };

    // Create an observer instance linked to the callback function
    const observer = new MutationObserver(observerCallback);

    // Start observing the target node for configured mutations
    observer.observe(targetNode, observerConfig);
    console.log("MutationObserver is watching for dynamic content to apply MathJax.");

    window.addEventListener('unload', () => {
        if (observer) {
            observer.disconnect();
            console.log("MutationObserver disconnected.");
        }
    });
}

// --- 2. Load MathJax ---
(function () {
    var script = document.createElement("script");
    script.type = "text/javascript";
    script.src = "https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS_HTML";
    script.async = true; // Load asynchronously without blocking page rendering
    document.getElementsByTagName("head")[0].appendChild(script);
    console.log("MathJax loading initiated.");
})();