(JS, defunct) Sketch of a Browser userscript for news.ycombinator.com

hackernews_comment_collapser.userscript.js

// ==UserScript==
// @name     HN Comment Collapse/Expd Button Injector
// @version  1
// @grant    none
// @namespace      http://userscripts.org/people/14536
// @description    Toggle all comments from collapsed to expanded state
// @match        https://news.ycombinator.com/*
// @author         Knut Behrends, ChatGPT
// ==/UserScript==
(function() {
    // Function to collapse all comments
    function collapseAllComments() {
        document.querySelectorAll("#hnes-comments > div header .collapser").forEach(elem => elem.click());
    }

    // Function to expand all comments
    function expandAllComments() {
        // You can replace this with the logic to expand all comments if it's different from the collapse logic
        // document.querySelectorAll("#hnes-comments > div header .collapser").forEach(elem => elem.click());
        //
        document.querySelectorAll("#hnes-comments > div header .collapser:not(section.replies .collapser)").forEach(elem => elem.click());
    }

    // Function to inject the "Collapse all" button
    function injectButton() {
        // Find the target element where the button should be appended
        let targetElem = document.querySelector("tr#content form");
        if (!targetElem) {
            targetElem = document.querySelector("table.fatitem tr:last-of-type");
            if (!targetElem) {
                console.warn("Target element not found!");
                return;
            }
        }

        // Create the "Collapse all" button
        let button = document.createElement("button");
        button.innerText = "Collapse all";
        button.style.marginTop = "25px"; // Add some margin for better spacing

        // Add click event listener to the button
        button.addEventListener("click", function(event) {
            event.preventDefault(); // Prevent any default button actions
            if (button.innerText === "Collapse all") {
                collapseAllComments();
                button.innerText = "Expand all";
            } else {
                expandAllComments();
                button.innerText = "Collapse all";
            }
        });

        // Append the button to the target element
        targetElem.appendChild(button);
    }

    // Execute the main logic
    injectButton();

})();