Phantom ghost-rejects valid transactions on devnet (popup doesn't load fully, error 4001)

[tdk333]

Summary

Hey team,

I've been hitting an intermittent issue where Phantom auto-rejects transactions on devnet after popup first starts to load then doesn't fully load. The user never gets a chance to approve or deny — it just fires back error 4001 ("User rejected the request") on its own.

Setup

• Phantom browser extension (latest, Chrome)
• @solana/kit v6.0.1 / @solana/react v6.0.1
• wallet-standard (solana:signAndSendTransaction feature)
• Solana devnet via Helius RPC
• Tested on multiple machines including a completely fresh install

What happens

When calling signAndSendTransaction through the wallet-standard interface, Phantom intermittently returns error 4001 without the approval popup fully loading.

The transaction itself is valid — simulating the exact same unsigned transaction on our Helius RPC with sigVerify: false passes every time.

Stack trace:

User rejected the request.
    at #n (solana.js:13:42651)
    at async r.signAndSendTransaction (solana.js:13:44864)
    at async #g [as signAndSendTransaction] (solana.js:13:49726)

What I've ruled out

• Transaction validity — simulation with sigVerify: false on Helius passes consistently after every rejection
• Wrong chain — explicitly passing chain: 'solana:devnet' (noticed Phantom reports solana:mainnet first in account.chains even when set to devnet)
• Our code — same behavior on two completely different codebases with different wallet-standard integration approaches
• Machine-specific issue — reproduced on a fresh computer with clean Chrome + fresh Phantom install
• signTransaction vs signAndSendTransaction — using signAndSendTransaction exclusively per Phantom's docs since signTransaction isn't supported in the wallet-standard implementation

What I think is happening

It seems like Phantom runs an internal simulation before rendering the approval popup. If that simulation is slow or fails (devnet RPC latency?), Phantom auto-rejects with 4001 before the user can interact. Since the same transaction simulates fine on other RPCs, the issue seems to be on Phantom's side — either devnet simulation infrastructure or some kind of timeout in the popup rendering pipeline.

The behavior is timing-dependent. It works more reliably when the popup renders quickly, and fails more often under load or when there's any delay.

Questions

1. Is this a known issue with Phantom's / devnet simulation?
2. Has anyone else been seeing this recently?

This started happening suddenly after months of it working fine. No changes on our end — even old code on old programs reproduces it now. Something seems to have changed upstream.

Any help appreciated.

Example

No response

Steps to Reproduce

To reproduce

1. Connect Phantom on devnet via wallet-standard
2. Build any valid devnet transaction using @solana/kit v6
3. Call signAndSendTransaction through the solana:signAndSendTransaction feature
4. Observe intermittent ghost rejections with no user interaction

Phantom Version

No response

Is there an existing discussion for this?

• I have searched the existing discussions