Lucence

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "name": "Lucence",
  "description": "View image transparency, the right way!",
  "version": "1.0",
  "manifest_version": 3,
  "web_accessible_resources": [
    {
      "resources": [
        "images/*",
        "*.css",
        "*.js",
        "*.png"
      ],
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "background": {
    "service_worker": "background.js"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*.png*",
        "*://*/*.svg*",
        "*://*/*.gif*"
      ],
      "run_at": "document_idle",
      "js": [
        "content-script.js"
      ]
    }
  ],
  "permissions": [
    "storage"
  ],
  "action": {
    "default_icon": {
      "128": "logo.png"
    }
  },
  "icons": {
    "128": "logo.png"
  }
}