google-chrome Chrome Extensions

Remarks

Browser Action running executeScript on a page.

manifest.json

{
  "name": "Hello Page",
  "description": "Add 'Hello' to the current page.",
  "version": "1.0",
  "permissions": [
    "activeTab"
  ],
  "background": {
    "scripts": ["background.js"],
    "persistent": false
  },
  "browser_action": {
    "default_title": "Say Hello on this page"
  },
  "manifest_version": 2
}

background.js

chrome.browserAction.onClicked.addListener(function(tab) {
  chrome.tabs.executeScript({
    code: 'document.body.insertAdjacentText("beforeBegin", "Hello!")'
  });
});