DeepSeek Smart Focus Manager

Autografts typing into the DeepSeek chat input on keypress, but blocks all other programmatic autofocus.

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name         DeepSeek Smart Focus Manager
// @description  Autografts typing into the DeepSeek chat input on keypress, but blocks all other programmatic autofocus.
// @match        https://chat.deepseek.com/*
// @run-at       document-start
// @version 0.0.1.20250512102624
// @namespace https://greasyfork.org/users/1435046
// ==/UserScript==

(function() {
  'use strict';

  //
  // 1) PREVENT all programmatic .focus() calls on TEXTAREA,
  //    *unless* the textarea has a special allowFocus flag.
  //
  const originalFocus = HTMLElement.prototype.focus;
  Object.defineProperty(HTMLElement.prototype, 'focus', {
    configurable: true,
    enumerable: true,
    writable: true,
    value: function(...args) {
      if (this.tagName === 'TEXTAREA') {
        // only allow if we've explicitly marked it
        if (this._allowDeepSeekFocus) {
          // consume the flag and focus
          delete this._allowDeepSeekFocus;
          return originalFocus.apply(this, args);
        }
        // otherwise swallow the focus()
        return;
      }
      // not a textarea => no change
      return originalFocus.apply(this, args);
    }
  });


  //
  // 2) AUTO-FOCUS & INJECT TEXT when you type anywhere on the page.
  //
  document.addEventListener('keydown', e => {
    // only letters/digits, not in an input already
    const active = document.activeElement;
    if (
      e.key.length === 1 &&
      /^[\w]$/i.test(e.key) &&
      !e.ctrlKey && !e.metaKey &&
      !(active && /^textarea|input$/i.test(active.tagName))
    ) {
      const textarea = document.getElementById('chat-input');
      if (!textarea) return;

      // prevent default so the page doesn’t try anything else
      e.preventDefault();

      // mark that *we* are allowed to focus it now
      textarea._allowDeepSeekFocus = true;
      textarea.focus();

      // insert the character where the cursor would go
      const start = textarea.selectionStart;
      const end   = textarea.selectionEnd;
      textarea.setRangeText(e.key, start, end, 'end');

      // notify React/MUI/etc.
      textarea.dispatchEvent(new Event('input',  { bubbles: true }));
      textarea.dispatchEvent(new Event('change', { bubbles: true }));
    }
  });
})();