Auto-fills Cat-a-lot edit summary on category-related pages

Classic_Edit_Summary_Autofill.js

// ==UserScript==
// @name         Wikipedia Classic Edit Summary Autofill
// @namespace    user-custom
// @version      1.0
// @description  Auto-fills Cat-a-lot edit summary on category-related pages
// @match https://en.wikipedia.org/wiki/Category:*
// @match https://en.wikipedia.org/w/index.php?search=*
// @match https://en.wikipedia.org/w/index.php?title=Category:
// @downloadURL  https://gist.githubusercontent.com/smasongarrison/cf44eb29a3c862ffccfbec1b97e9e114/raw/Classic_Edit_Summary_Autofill.js
// @updateURL    https://gist.githubusercontent.com/smasongarrison/cf44eb29a3c862ffccfbec1b97e9e114/raw/Classic_Edit_Summary_Autofill.js
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    const selector = '#cat_a_lot_comment';
    const stringToInsert = 'Diffusing per [[WP:DIFFUSE]] and/or [[WP:ALLINCLUDED]]';

    setTimeout(() => {
        const box = document.querySelector(selector);
        if (box && !box.value.trim()) {
            box.value = stringToInsert;
        }
    }, 1400); // wait 1.4 seconds
})();