The wallet WebSocket handler assumed LNbits sends the PRE-payment balance
for outgoing payments and subtracted the amount again. LNbits actually
re-fetches the wallet AFTER the payment settles before emitting the
notification (core payments.py `_send_payment_notification_in_background`
→ "fetch balance again" → notifications.py `send_ws_payment_notification`
→ `wallet.balance`), so `wallet_balance` is already POST-payment for both
directions. The extra subtraction double-deducted: 100 sats, send 10 →
balance showed 80, then a refresh (which reads the authoritative
/api/v1/wallet balance) corrected it to 90.
Use `wallet_balance` as-is for all messages, matching the polling
fallback which already trusts the API balance directly.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
