Examine source code of Replaycer

{
  "manifest_version": 2,
  "name": "Replaycer",
  "description": "Have fun by replacing text for the web",
  "homepage_url": "https://github.com/amar-laksh/Replaycer",
  "version": "1.2resigned1",
  "icons": {
    "48": "icons/icon.png"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/icon.png",
    "default_title": "Replaycer",
    "default_popup": "popup/replace_text.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4da3a448-ddc6-424a-a5c8-5af27c3516ac}"
    }
  }
}