Force Select All + Copy Text

Selects all text on the page and copies it to clipboard with a button click
换行
// ==UserScript==
// @name         Force Select All + Copy Text
// @namespace    http://tampermonkey.net/
// @version      1.0
// @description  Selects all text on the page and copies it to clipboard with a button click
// @match        *://*/*
// @grant        clipboardWrite
// @run-at       document-idle
// ==/UserScript==

(function () {
  'use strict';

  const btn = document.createElement('button');
  btn.textContent = 'Select / Copy';
  btn.style.cssText = `
    position: fixed;
    bottom: 18px;
    right: 18px;
    z-index: 2147483647;
    padding: 10px 14px;
    border-radius: 999px;
    border: none;
    background: #111;
    color: white;
    font-size: 14px;
    font-family: -apple-system, BlinkMacSystemFont, sans-serif;
    box-shadow: 0 4px 18px rgba(0,0,0,.35);
  `;

  btn.addEventListener('click', async () => {
    try {
      const selection = window.getSelection();
      const range = document.createRange();

      range.selectNodeContents(document.body);
      selection.removeAllRanges();
      selection.addRange(range);

      const text = document.body.innerText || document.documentElement.innerText || '';

      if (navigator.clipboard && text.trim()) {
        await navigator.clipboard.writeText(text);
        btn.textContent = 'Copied';
      } else {
        btn.textContent = 'Selected';
      }

      setTimeout(() => {
        btn.textContent = 'Select / Copy';
      }, 1400);
    } catch (err) {
      btn.textContent = 'Blocked';
      setTimeout(() => {
        btn.textContent = 'Select / Copy';
      }, 1400);
    }
  });

  document.documentElement.appendChild(btn);
})();