Examine source code of Send to Discord

{
  "name": "Send to Discord",
  "version": "1.2.2",
  "description": "Quickly send links to Pages, Images, Text-Selections, etc. to a Discord channel via a WebHook",
  "manifest_version": 2,
  "homepage_url": "https://github.com/burgha/sendtodiscord",
  "permissions": [
    "contextMenus",
    "storage",
    "identity",
    "https://discordapp.com/api/"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "browser_action": {
    "default_icon": {
      "16": "icon16.png",
      "48": "icon48.png",
      "128": "icon128.png"
    },
    "default_popup": "popup.html"
  }
}