Putting address generation behind a generate button is a very good idea. I'll have to change the template message too. Instead of "you received money" it will have to say "maybe you received money" or similar.

supertestnet

bitcoin

Whisper Addresses: Privacy preserving automatic bitcoin address generation in vanilla javascript

You could also put the sender instantiation behind a "generate" button to avoid creating a nostr message for every page load. I want to avoid spamming nostr as well but luckily the traffic will be coming from the client so relay anti-spam prevention can be applied.