Examine source code of Line Reverse & Text Trim

{
  "version": "1.0.3",
  "manifest_version": 2,
  "name": "Line Reverse & Text Trim",
  "description": "Tool for trimming and reversing lines. Assets donated by 'Pixel perfect' (https://www.flaticon.com/authors/pixel-perfect).",
  "icons": {
    "64": "icons/addon-icon-64.png"
  },
  "browser_action": {
    "browser_style": true,
    "default_popup": "popup/popup.html",
    "default_icon": {
      "64": "icons/addon-icon-64.png"
    }
  },
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{f3305ea1-0494-40cc-8f1e-b61d7095c223}"
    }
  }
}