Examine source code of Simage

{
  "manifest_version": 2,
  "name": "__MSG_extnName__",
  "description": "__MSG_extnDescription__",
  "version": "1.0.6",
  "default_locale": "en",
  "applications": {
    "gecko": {
      "id": "LDSMGweb_plashcor@gmail.com",
      "strict_min_version": "58.0"
    }
  },
  "permissions": [
    "<all_urls>",
    "menus",
    "contextMenus",
    "notifications",
    "storage",
    "tabs",
    "downloads",
    "alarms"
  ],
  "browser_action": {
    "default_icon": "icons/24-simage.png",
    "default_title": "__MSG_extnName__",
    "browser_style": true
  },
  "background": {
    "scripts": [
      "smg_com.js",
      "options/settings.js",
      "smg_bkgd.js"
    ]
  },
  "content_scripts": [
    {
      "all_frames": false,
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "smg_content.js"
      ],
      "run_at": "document_start"
    },
    {
      "all_frames": true,
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "smg_cnt_imgs.js"
      ],
      "run_at": "document_start"
    }
  ],
  "icons": {
    "24": "icons/24-simage.png",
    "32": "icons/32-simage.png",
    "48": "icons/48-simage.png",
    "64": "icons/64-simage.png"
  },
  "options_ui": {
    "page": "options/options.html",
    "browser_style": true,
    "open_in_tab": true
  },
  "commands": {
    "SMG:open-options": {
      "suggested_key": {
        "default": "Ctrl+Shift+O"
      },
      "description": "Open 'Simage' options page"
    },
    "SMG:save-mouse": {
      "suggested_key": {
        "default": "Ctrl+Shift+Z"
      },
      "description": "Save the image under the mouse"
    }
  }
}