Examine source code of r/Slash

{
  "manifest_version": 2,
  "name": "r/Slash",
  "version": "1.0.0",
  "description": "Redirects r/… from the URL bar or search engines to the respective subreddit.",
  "icons": {
    "48": "icons/icon.svg",
    "96": "icons/icon.svg"
  },
  "permissions": [
    "webNavigation"
  ],
  "background": {
    "scripts": [
      "scripts/background.js"
    ]
  },
  "omnibox": {
    "keyword": "r/"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "rslash@elypia.org"
    }
  }
}