Disable HDR emojis in Google Chat

disable-hdr-emojis.user.js

// ==UserScript==
// @name         Disable HDR Emojis in Google Chat
// @namespace    http://tampermonkey.net/
// @version      1.1
// @description  Clamp custom emoji brightness to disable HDR/bloom effects in Google Chat.
// @author       Alexey Shevchenko
// @match        https://chat.google.com/*
// @grant        GM_addStyle
// ==/UserScript==

(function () {
    'use strict';

    // Custom emoji images sometimes have a brightness filter applied that produces
    // an HDR/bloom effect. Clamping brightness to 1 disables that effect.
    GM_addStyle(`
        img[data-shortcode^=':'][data-shortcode$=':'][src*='/api/get_custom_emoji_image?'],
        img[alt^=':hdr-'][src*='/api/get_custom_emoji_image?'] {
            filter: brightness(1) !important;
        }
    `);
})();