Examine source code of Tweaks for VSCO

{
  "name": "Tweaks for VSCO",
  "manifest_version": 2,
  "description": "View and download full-size images on vsco.co website. Includes custom gallery viewer - change theme, thumbnail size, and more.",
  "browser_specific_settings": {
    "gecko": {
      "id": "{7fcff281-c0ed-48a6-85b9-e9d2ba2ecd13}"
    }
  },
  "page_action": {
    "default_title": "Tweaks for VSCO",
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icon-16.png",
      "19": "icon-19.png",
      "24": "icon-24.png",
      "32": "icon-32.png",
      "38": "icon-38.png",
      "48": "icon-48.png",
      "96": "icon-96.png"
    },
    "show_matches": [
      "https://vsco.co/*"
    ]
  },
  "background": {
    "scripts": [
      "background.bundle.js"
    ]
  },
  "commands": {
    "_execute_page_action": {
      "description": "Open Popup"
    }
  },
  "icons": {
    "16": "icon-16.png",
    "19": "icon-19.png",
    "24": "icon-24.png",
    "32": "icon-32.png",
    "38": "icon-38.png",
    "48": "icon-48.png",
    "96": "icon-96.png"
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "permissions": [
    "storage",
    "downloads"
  ],
  "version": "3.7.0",
  "content_scripts": [
    {
      "js": [
        "content.custom-styles.bundle.js"
      ],
      "matches": [
        "https://vsco.co/*"
      ],
      "run_at": "document_start"
    },
    {
      "js": [
        "content.vsco.bundle.js"
      ],
      "matches": [
        "https://vsco.co/*"
      ],
      "run_at": "document_end"
    }
  ]
}