Instafact Go - A fact on every page Firefox

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manifest.json
{
  "manifest_version": 2,
  "name": "Instafact Go - A fact on every page",
  "short_name": "Instafact Go",
  "version": "1.0.4",
  "description": "Instafact Go is an unobtrusive way to learn about interesting facts while you are browsing the web",
  "background": {
    "persistent": true,
    "scripts": [
      "background.js"
    ]
  },
  "applications": {
    "gecko": {
      "id": "extension@instafact-go",
      "strict_min_version": "54.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "contentScript.js"
      ],
      "all_frames": false,
      "run_at": "document_end"
    }
  ],
  "browser_action": {
    "default_title": "Instafact Go",
    "default_popup": "popup.html"
  },
  "icons": {
    "32": "icons/32.png",
    "48": "icons/48.png",
    "96": "icons/96.png",
    "128": "icons/128.png"
  },
  "permissions": [
    "storage",
    "unlimitedStorage",
    "tabs"
  ]
}

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