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(c/p from Mutiny)

Force-Closes:

Force-closes on Lightning happen when there's a communication problem between two nodes, or one goes offline, and the other node needs to close a channel. We've run into several force-close bugs during closed beta and fixed many of them this week. However, it never feels good to pay for a lightning channel and have that close, even if it's weeks later. We've seen that most channels are not force closing, but the few that have is no fun. Funds may lock up for three or more days when it happens.

We’ve fixed every bug we’ve identified, but there are still potential hidden problems due to the complexity of Lightning. Because of this, we express some caution when opening large channels while we are still in beta.

On-Chain Balances:

Sometimes when the app reloads, it may need to recheck the blockchain for all your on-chain transactions. So while this happens, it may show a 0 balance for up to a minute while it resyncs. We admit it is scary to see 0, but we're working to ensure that displaying balances persist across restarts without needing to sync again.