KoalaSync/extension/tab-filter.js

function hostnameMatchesDomain(hostname, domain) {
    const normalizedHostname = String(hostname || '').toLowerCase();
    const normalizedDomain = String(domain || '').toLowerCase();
    return normalizedDomain
        && (normalizedHostname === normalizedDomain
            || normalizedHostname.endsWith(`.${normalizedDomain}`));
}

export function isTabUrlFiltered(url, blacklistDomains, allowlistDomains = []) {
    const urlString = String(url || '');

    try {
        const hostname = new URL(urlString).hostname.toLowerCase();
        if (allowlistDomains.some(domain => hostnameMatchesDomain(hostname, domain))) {
            return false;
        }
        return blacklistDomains.some(domain => hostnameMatchesDomain(hostname, domain));
    } catch {
        const normalizedUrl = urlString.toLowerCase();
        return blacklistDomains.some(domain => normalizedUrl.includes(String(domain).toLowerCase()));
    }
}