Custom Timezone Offset

manifest.json

{
  "manifest_version": 2,
  "name": "Custom Timezone Offset",
  "version": "0.0.4",
  "description": "Adjust RFP UTC time to match local time without giving away your real timezone",
  "developer": {
    "name": "defkev"
  },
  "applications": {
    "gecko": {
      "id": "custom-timezone-offset@defkev",
      "strict_min_version": "54.0"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "32": "history-solid-light.svg"
    },
    "theme_icons": [
      {
        "light": "history-solid-light.svg",
        "dark": "history-solid.svg",
        "size": 32
      }
    ]
  },
  "options_ui": {
    "page": "options.html"
  },
  "permissions": [
    "<all_urls>",
    "alarms",
    "storage",
    "webNavigation"
  ]
}