Examine source code of Simple Element Blocker

{
  "manifest_version": 2,
  "name": "Element Blocker",
  "version": "1.0.0",
  "description": "Block unwanted elements on web pages",
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "element-blocker@yourdomain.com",
      "strict_min_version": "58.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_action": {
    "default_title": "Element Blocker",
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  }
}