Examine source code of Save screenshot and image

{
  "manifest_version": 2,
  "version": "0.7.0",
  "name": "__MSG_extName__",
  "description": "__MSG_extDescription__",
  "author": "nepon",
  "default_locale": "en",
  "applications": {
    "gecko": {
      "id": "saveimage@aime",
      "strict_min_version": "56.0"
    }
  },
  "permissions": [
    "<all_urls>",
    "activeTab",
    "contextMenus",
    "notifications",
    "downloads",
    "storage"
  ],
  "background": {
    "scripts": [
      "common/common.js",
      "download.js",
      "buildSubMenus.js",
      "saveimage-bg.js",
      "capture-bg.js"
    ]
  },
  "icons": {
    "16": "images/camera4-16.png",
    "32": "images/camera4.svg"
  },
  "browser_action": {
    "default_icon": {
      "16": "images/camera4-16.png",
      "32": "images/camera4.svg"
    },
    "default_title": "__MSG_actionTitle__",
    "default_popup": "popup/popup.html",
    "browser_style": true
  },
  "commands": {
    "capture-visible": {
      "description": "__MSG_commandCaptureVisibleArea__"
    },
    "capture-all": {
      "description": "__MSG_commandCaptureAll__"
    }
  },
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": true,
    "browser_style": false
  }
}