Simple Chrome extension

background.js

var toggle = false;

chrome.browserAction.onClicked.addListener(function (tab) {
  toggle = !toggle;
  if (toggle){
    // chrome.browserAction.setIcon({path: "on.png", tabId:tab.id});
    chrome.tabs.executeScript(tab.id, {file: "color-picker.js"});
  } else {
    //chrome.browserAction.setIcon({path: "off.png", tabId:tab.id});
    //chrome.tabs.executeScript(tab.id, {code: "alert('hello')"});
    chrome.tabs.executeScript(tab.id, {file: "quit.js"});
  }
});

color-picker.js

(function () {
  const div = document.createElement('div');

  div.id = 'jeantimex';
  div.innerHTML = 'test';
  document.body.appendChild(div);
})();

manifest.json

{
  "name": "Append Test Text",
  "description": "Add test123 to body",
  "version": "1.0",
  "permissions": [
    "activeTab"
  ],
  "background": {
    "scripts": ["background.js"] 
  },
  "browser_action": {
    "default_title": "Append Test Text"
  },
  "manifest_version": 2
}

quit.js

(function () {
  const div = document.querySelector('#jeantimex');
  if (div) {
    div.remove();
  }
})();