Examine source code of Shift Guard

{
  "manifest_version": 2,
  "name": "Shift Guard",
  "description": "Prevent accidental clicks on recently shifted content by opening a prompt asking whether to continue.",
  "version": "0.0.4",
  "icons": {
    "64": "icons/icon-64.png",
    "128": "icons/icon-128.png",
    "512": "icons/icon-512.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content-scripts/main.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": {
      "64": "icons/icon-64.png"
    },
    "default_title": "Configure Shift Guard",
    "default_popup": "popup/index.html"
  },
  "options_ui": {
    "page": "popup/index.html",
    "browser_style": false
  },
  "background": {
    "scripts": [
      "/background/main.js"
    ],
    "type": "module"
  },
  "permissions": [
    "<all_urls>",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{3aad82ed-58b9-44c8-9057-b265ded8c9f9}"
    }
  }
}