Examine source code of Keep It Flow

{
  "browser_specific_settings": {
    "gecko": {
      "strict_min_version": "58.0a1",
      "id": "{fa09f6aa-bed0-45e8-ae7b-e4a781c09027}"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "browser_style": true,
    "default_title": "Keep it flow",
    "default_popup": "popup.html"
  },
  "description": "This extension will help you focus while managing the sounds in the background.",
  "icons": {
    "16": "icons/Icon16.png",
    "48": "icons/Icon48.png",
    "128": "icons/Icon128.png"
  },
  "manifest_version": 2,
  "name": "Keep it flow",
  "permissions": [
    "tabs",
    "storage"
  ],
  "version": "1.2"
}