QRegularExpression emails(R"([A-Z0-9a-z._-]{1,}@(\w+)\.(\w+)(?:\.(\w+))?)");
auto matches = emails.globalMatch(html);
while (matches.hasNext()) {
    auto match = matches.next();
    if (match.hasMatch()) {
        auto email = match.captured(0);
    }
}