Examine source code of Clear Downloads

{
  "manifest_version": 2,
  "name": "Clear Downloads Plugin",
  "description": "This extension will allow you to clear your downloads with one click",
  "homepage_url": "https://github.com/premnirmal/ClearDownloadsPlugin",
  "version": "1.1resigned1",
  "icons": {
    "48": "icons/icon48.png"
  },
  "permissions": [
    "downloads"
  ],
  "browser_action": {
    "browser_style": true,
    "default_popup": "popup/cleared_message.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon48.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{09d78f21-ff8f-426d-bee4-f97438ba864e}"
    }
  }
}