that's why this exists:
https://chromewebstore.google.com/detail/plebeian-signer-nostr-ide/ijbiankmnehjephbkfdgphckcdgbgoho?authuser=0&hl=enjust about to bump a bunch of changes including a feature that lets you keep the nsec available to the extension when you restart, if you enable the "stay unlocked" setting.
and yeah, as i say, just open
https://smesh.mleku.dev after opening the dev console to see just how much fetching and decryption goes on, and i have bugger all DMs in my log.
for this reason also, i created a "delete" function which basically sets the newest timestamp to bother fetching to save on that, so you can "delete" messages, and what that means in practice is it just doesn't look for any messages before the moment you click that button.
i'm no spring chicken when it comes to cryptography or pipelines or concurrency. if you are new to it i can totally understand why you are reluctant. i suggest you may find it useful to look at the codebase
https://git.mleku.dev/mleku/smesh - or not, up to you.
people underestimate me because they think that networks, cryptography, distributed systems, and all that stuff, is voodoo. they think javascript is the be-all and end-all of programming, and they disregard everything i say.
don't be like these people.