Examine source code of tackup

{
  "manifest_version": 2,
  "name": "tackup",
  "version": "0.5.1",
  "author": "наб <nabijaczleweli.xyz>",
  "homepage_url": "https://github.com/nabijaczleweli/tackup",
  "description": "Continuously back up your browser tabs.",
  "icons": {
    "48": "assets/icons/tackup-48.png",
    "96": "assets/icons/tackup-96.png"
  },
  "applications": {
    "gecko": {
      "id": "tackup@nabijaczleweli.xyz",
      "strict_min_version": "58.0"
    }
  },
  "permissions": [
    "tabs",
    "storage",
    "unlimitedStorage"
  ],
  "background": {
    "scripts": [
      "src/tackup.js"
    ]
  },
  "options_ui": {
    "page": "assets/pages/config/index.html"
  },
  "browser_action": {
    "default_icon": {
      "19": "assets/icons/tackup-19.png",
      "38": "assets/icons/tackup-38.png"
    },
    "default_title": "View/edit tab backups"
  }
}