Examine source code of Femmage

{
  "manifest_version": 2,
  "name": "Collage",
  "version": "0.1",
  "description": "Make any web page a canvas to select, copy and paste anywhere else.",
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "src/content.js",
        "src/content/css.js",
        "src/content/clip.js",
        "src/content/paste.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "src/background.js"
    ]
  },
  "permissions": [
    "activeTab",
    "<all_urls>",
    "clipboardWrite"
  ]
}