Examine source code of KepiCache Cleaner

{
  "manifest_version": 3,
  "name": "KepiCache Cleaner",
  "description": "Lightweight cache cleaner for Firefox",
  "version": "1.0.0",
  "browser_specific_settings": {
    "gecko": {
      "id": "kepicachecleaner@example.com"
    }
  },
  "permissions": [
    "browsingData",
    "tabs"
  ],
  "action": {
    "default_icon": {
      "48": "ico_48.png",
      "96": "ico_96.png"
    },
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "commands": {
    "clear-cache": {
      "suggested_key": {
        "default": "F9"
      },
      "description": "Clear cache"
    }
  },
  "icons": {
    "48": "ico_48.png",
    "96": "ico_96.png"
  }
}