popup.js

/* eslint-disable no-undef */
// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

const changeColor = document.getElementById('changeColor');
chrome.storage.sync.get('color', (data) => {
  changeColor.style.backgroundColor = data.color;
  changeColor.setAttribute('value', data.color);
});

changeColor.onclick = function (element) {
  const color = element.target.value;
  chrome.tabs.query({ active: true, currentWindow: true }, (tabs) => {
    chrome.tabs.executeScript(
      tabs[0].id,
      { code: `document.body.style.backgroundColor = "${color}";` },
    );
  });
};