Restore native Shift+Arrow text selection behavior in ChatGPT message editors

chatgpt-shift-arrow-selection-restore-console-test-snippet.js

// Natural Selection - Console Test Snippet - Extension here: https://github.com/banagale/natural-selection
// Restores native Shift+Arrow text selection in ChatGPT editors
(() => {
  'use strict';

  let guardUntil = 0;
  const arm = (ms) => guardUntil = performance.now() + ms;
  const active = () => performance.now() < guardUntil;
  let currentEditor = null;

  const isTypingEl = (el) => {
    if (!el) return false;
    return (
      el.tagName === 'TEXTAREA' ||
      el.tagName === 'INPUT' ||
      el.isContentEditable ||
      el.getAttribute?.('role') === 'textbox'
    );
  };

  window.addEventListener('keydown', (e) => {
    if (e.shiftKey && (e.key === 'ArrowUp' || e.key === 'ArrowDown')) {
      currentEditor = isTypingEl(e.target) 
        ? e.target 
        : e.target.closest?.('[contenteditable="true"], textarea, [role="textbox"]');
      
      if (currentEditor) {
        e.stopImmediatePropagation();
        console.log(`✓ Blocked ChatGPT's Shift+${e.key} handler`);
      }
      arm(400);
    }
  }, true);

  window.addEventListener('keyup', (e) => {
    if (e.shiftKey && (e.key === 'ArrowUp' || e.key === 'ArrowDown')) {
      const editor = isTypingEl(e.target) 
        ? e.target 
        : e.target.closest?.('[contenteditable="true"], textarea, [role="textbox"]');
      
      if (editor) {
        e.stopImmediatePropagation();
      }
    }
    
    if (e.key === 'ArrowUp' || e.key === 'ArrowDown') {
      arm(350);
      requestAnimationFrame(() => arm(150));
    }
  }, true);

  const origScrollIntoView = Element.prototype.scrollIntoView;
  Element.prototype.scrollIntoView = function(...args) {
    if (active() && this.tagName === 'ARTICLE') {
      console.log('✓ Blocked unwanted scroll');
      return;
    }
    return origScrollIntoView.apply(this, args);
  };

  const origFocus = HTMLElement.prototype.focus;
  HTMLElement.prototype.focus = function(...args) {
    if (active() && currentEditor) {
      if (this !== currentEditor && !currentEditor.contains(this) && !this.contains(currentEditor)) {
        console.log('✓ Blocked focus theft');
        return;
      }
    }
    return origFocus.apply(this, args);
  };

  console.log('✓ Natural Selection loaded! Try Shift+Arrow text selection now.');
})();