Examine source code of Tempo Tracker

{
  "name": "Tempo-Tracker",
  "version": "3.13.2",
  "manifest_version": 2,
  "description": "Timetracker with synchronization to the Jira Tempo-Plugin.",
  "icons": {
    "16": "icon16.png",
    "19": "icon19.png",
    "32": "icon32.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "tempo-tracker@fochlac.com"
    }
  },
  "background": {
    "scripts": [
      "./sw.js"
    ],
    "persistent": true
  },
  "commands": {
    "stop_tracking": {
      "suggested_key": {
        "default": "Ctrl+Shift+0"
      },
      "description": "Stop Tracking"
    },
    "start_tracking_1": {
      "suggested_key": {
        "default": "Ctrl+Shift+1"
      },
      "description": "Start Tracking for Issue 1"
    },
    "start_tracking_2": {
      "suggested_key": {
        "default": "Ctrl+Shift+2"
      },
      "description": "Start Tracking for Issue 2"
    },
    "start_tracking_3": {
      "suggested_key": {
        "default": "Ctrl+Shift+3"
      },
      "description": "Start Tracking for Issue 3"
    }
  },
  "permissions": [
    "alarms",
    "<all_urls>",
    "menus",
    "scripting"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "content-script.js"
      ]
    },
    {
      "matches": [
        "https://wd5.myworkday.com/*"
      ],
      "js": [
        "workday-script.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": {
      "19": "icon19.png",
      "32": "icon32.png",
      "48": "icon48.png",
      "128": "icon128.png"
    },
    "default_popup": "popup.html"
  },
  "web_accessible_resources": [
    "https://wd5.myworkday.com/*"
  ]
}