Examine source code of JIRA Oldest First

{
  "manifest_version": 2,
  "name": "JIRA Oldest First",
  "version": "0.2",
  "author": "Andreas Grill",
  "description": "Adds query string to URL to set Action Order to Ascending - use case for JIRA have Oldest First as standard.",
  "icons": {
    "48": "jira_of_ag48.png",
    "128": "jira_of_ag128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html"
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "https://*/*?*",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "jira_oldest_first@jof.at"
    }
  }
}