Dropbox button

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 3,
  "name": "Dropbox button",
  "version": "15.0",
  "description": "Main links to Dropbox.",
  "icons": {
    "128": "icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "functions.js"
      ]
    }
  ],
  "action": {
    "default_title": "Dropbox button",
    "default_icon": "icon.png",
    "default_popup": "background.html"
  }
}