manifest.json

{
    "name": "Price finder",
    "description": "Find prices.",
    "version": "0.0.1",
    "manifest_version": 3,
    "options_page": "html/options.html",
    "background": {
        "service_worker" : "js/service-workers/background.js"
    },
    "action": {
        "default_popup": "html/popup.html"
    },
    "permissions": [
        "contextMenus",
        "activeTab",
        "storage",
        "scripting"
    ],
    "content_scripts": [
        {
            "run_at": "document_idle",
            "matches": [
                "https://*.ebay.com/*", 
                "https://*.amazon.com/*",
                "https://*.bestbuy.com/*",
                "https://*.walmart.com/*",
                "https://*.newegg.com/*"
            ],
            "js": [
                "/js/content-scripts/content-script.js", 
                "/js/content-scripts/read-store-element.js"
            ]
        }
    ],
    "web_accessible_resources": [
        {
            "resources": ["/resources/*"], 
            "matches": ["https://web-accessible-resources-2.glitch.me/*"]
        }
    ]
}