Examine source code of Tabs Hotkeys

{
  "manifest_version": 2,
  "name": "Tabs Hotkeys",
  "description": "Hotkeys for tabs navigation",
  "version": "1.1",
  "applications": {
    "gecko": {
      "id": "firefox-tab-hotkeys@alex0007",
      "strict_min_version": "60.0"
    }
  },
  "developer": {
    "name": "Alex0007",
    "url": "https://github.com/Alex0007/"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "128": "icons/icon128.png"
  },
  "commands": {
    "pin-tab": {
      "suggested_key": {
        "default": "Ctrl+Alt+P"
      },
      "description": "Pin active tab"
    },
    "left-tab": {
      "suggested_key": {
        "default": "Ctrl+Shift+Left"
      },
      "description": "Switch to tab to the left"
    },
    "right-tab": {
      "suggested_key": {
        "default": "Ctrl+Shift+Right"
      },
      "description": "Switch to tab to the right"
    }
  },
  "content_scripts": [
    {
      "all_frames": false,
      "js": [
        "shortcuts.js"
      ],
      "matches": [
        "http://*/*",
        "https://*/*",
        "file:///*"
      ],
      "run_at": "document_start"
    }
  ],
  "permissions": [
    "tabs",
    "http://*/*",
    "https://*/*"
  ]
}