That is useful, but how do you manage to remember the mappings? I want to know what random string corresponds to what service without having to search my passwo

That is useful, but how do you manage to remember the mappings? I want to know what random string corresponds to what service without having to search my password manager. The best of both worlds would be random local part + a Chrome extension that manages the mappings. The Chrome extension can then replace the local part in Google Inbox with the corresponding site name.