Decrypting DMs is an issue with any remote signer that uses NIP-46, because each decrypt request has to round-trip over a relay for every single message. And modern (NIP-17) DMs are giftwrapped, so each message is roughly two decrypt requests instead of one — the client has to unwrap the giftwrap and then the seal, both round-tripping to Clave. So an npub with a few thousand messages (totally possible) means several thousand round-trips, which can take a few minutes even in the best case. @Clave connects directly to relays when the app is foregrounded and processes requests in parallel, so if you're logging into a client for the first time, I'd recommend keeping Clave open (obviously a challenge if the client is on the same device). When Clave is backgrounded, it goes through the iOS notification service extension, which is more constrained — iOS gives each wake a hard ~30s budget and only a handful of requests get handled per wake, so a big backlog can stall and take much longer. Foregrounding is by far the faster path. Ultimately though, it's up to clients that support DMs and NIP-46 to figure out ways to avoid trying to decrypt an entire DM inbox over the wire in one shot.