Fixing ChatGPT "Lost First Key" Bug in Firefox

Problem

When using ChatGPT in Firefox, the text input field doesn’t properly register the first typed character. The cursor appears focused, but the first keypress is ignored, making it frustrating to start typing. In Chromium browsers, this issue doesn’t occur — the first keystroke goes directly into the input field as expected.

Solution

This happens because ChatGPT’s web app uses React and dynamic rendering, and Firefox handles DOM focus and event propagation slightly differently. React’s internal focus management can interfere, causing the first keystroke to be lost. A workaround is to programmatically focus the textarea when it appears and, if needed, simulate user interaction (like a click) to ensure the input field is truly active.

Instruction

You can create a userscript to fix this in Firefox using Tampermonkey or Violentmonkey. The script observes the page’s DOM for changes, and when the textarea appears, it forces focus on it. Additionally, it simulates a mouse click event in the center of the textarea to activate the input fully.

Here’s a userscript example:

// ==UserScript==
// @name         ChatGPT Firefox Input Focus Fix
// @namespace    http://tampermonkey.net/
// @version      1.0
// @description  Fixes lost first keystroke in ChatGPT input on Firefox by focusing and clicking the textarea
// @match        https://chat.openai.com/*
// @match        https://chatgpt.com/*
// @grant        none
// ==/UserScript==

(function () {
  const simulateClick = (el) => {
    const rect = el.getBoundingClientRect();
    const x = rect.left + rect.width / 2;
    const y = rect.top + rect.height / 2;
    ["mousedown", "mouseup", "click"].forEach(type => {
      el.dispatchEvent(new MouseEvent(type, {
        bubbles: true,
        cancelable: true,
        view: window,
        clientX: x,
        clientY: y,
      }));
    });
  };

  const tryFocusByClick = () => {
    const input = document.querySelector("textarea");
    if (input && document.activeElement !== input) {
      simulateClick(input);
    }
  };

  const observer = new MutationObserver(() => {
    tryFocusByClick();
  });

  observer.observe(document.body, {
    childList: true,
    subtree: true,
  });

  window.addEventListener("load", () => {
    setTimeout(tryFocusByClick, 150);
  });

  document.addEventListener("visibilitychange", tryFocusByClick);
})();

To use it:

• Install Tampermonkey or Violentmonkey in Firefox.
• Create a new userscript and paste the above code.
• Save and reload ChatGPT in Firefox.

Result

After applying this userscript, the textarea in ChatGPT on Firefox will receive proper focus, and the first keypress won’t be lost. You should be able to start typing immediately without needing to press Enter or click the field manually. This significantly improves the input experience on Firefox, bringing it closer to Chromium’s behavior.

Tested on Firefox 135

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