Examine source code of BioStudies button

{
  "manifest_version": 2,
  "name": "BioStudies button",
  "version": "0.0.2",
  "description": "Search the BioStudies database for data packages associated to publications.",
  "author": "David Miguel Susano Pinto",
  "homepage_url": "https://github.com/carandraug/biostudies-button",
  "icons": {
    "48": "images/biostudies-icon.svg",
    "96": "images/biostudies-icon.svg"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_area": "navbar",
    "default_icon": "images/biostudies-icon.svg",
    "default_title": "BioStudies",
    "default_popup": "popup/index.html"
  }
}