manifest.json

{
    "manifest_version": 3,
    "name": "Nostalgia Sepia Theme",
    "version": "1.1",
    "description": "Adds a sepia filter to images, text glow with vintage font styling.",
    "permissions": ["storage", "scripting", "tabs"],
    "background": {
    "service_worker": "background.js"
  	},
    "action": {
      "default_popup": "popup.html",
      "default_icon": "icon.png"
    },
    "content_scripts": [
      {
        "matches": ["<all_urls>"],
        "js": ["content.js"],
        "run_at": "document_idle"
      }
    ],
    "web_accessible_resources": [
      {
        "resources": ["caslon-antique.woff2"],
        "matches": ["<all_urls>"]
      }
    ]
  }