It *could* be web wallet communicating with nostr/lnurl servers, mints and relays.

Just keep in mind that to keep the wallet state safe and working, web is far from ideal.

For instance, Minibits uses 2 separate storage technologies (mmkv as fast read/write, sqlite as append only backup) to prevent / recover from storage failures. This is not possible on the web. Safe keys store is as well big challenge on the web.