Examine source code of Video Blocker

{
  "manifest_version": 2,
  "name": "Video Blocker",
  "version": "1.8",
  "description": "Blocks all videos on all websites.",
  "permissions": [
    "scripting",
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end",
      "all_frames": true
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "video.blocker@c0d3d3v",
      "strict_min_version": "58.0"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  }
}