Remove RBF from user visible settings

Bitcoin 24.0 adds a new mempoolfullrbf option that allows for replace-by-fee even if the original transaction didn’t set the RBF flag.

Currently, the get_tx_info and dscancel functions only consider a double-spend-cancel viable if the transaction has the RBF flag set (i.e. if not tx.is_final()).
As the linked release notes mention, full RBF will now be a mainstream feature even though many alternate implementations have supported it for a while. Either is_final() should always return False or it should depend on if the transaction has been confirmed or not.

[ecdsa]

All right. I don’t know if bumping the fee of transactions imported from non-Electrum wallets is what the OP had in mind, but I consider that as out of scope. If we have an opportunity to simplify the UX, we should take it. Nothing beats the satisfaction of removing a few check boxes from the GUI.

Regarding channel funding, we can keep using the RBF flag as a way to prevent an accidental fee bumping from another instance of the same wallet. As you point out, that solution is not going to work with channel v2, so we will need to address that separately.

[SomberNight]

I would prefer if we removed the current RBF checkbox in the UI, and we made all our transactions RBF signalling. That would simplify the UX, instead of making it more complex.

Sure, that’s fine, at this point I think we can do that. However, note it does not address OP’s point with opening this issue:

replace-by-fee even if the original transaction didn’t set the RBF flag.

Even if we make sure all of the transactions we create signal RBF, if a user restores a wallet with pre-existing unconfirmed txs created elsewhere, the question is whether we want to allow RBF-ing those. Also, note that we don’t always signal RBF atm, e.g. for channel funding txs (see https://github.com/spesmilo/electrum/issues/7072).

RBF-ing a non-signalling tx is highly probabilistic atm. First and foremost, I am sure many electrum servers are backed by bitcoinds with default mempoolfullrbf=false, sending an error to the client if it tried to RBF such a tx. Even when using an electrum server that has mempoolfullrbf=true, propagation in the p2p network is not guaranteed and is totally opaque to the client (even to bitcoind). So, atm, if we wanted to allow RBF-ing non-signalling txs, we would either need to hide it behind an advanced option, or give proper warnings and explanation to the user.

(note: power-users can atm RBF non-signalling txs by using the Qt console to call wallet.adb.remove_transaction(txid) and then creating a replacement normally (but making sure it conflicts with the old tx) - this is what I had done multiple times over the years when needing this, and also instructed some users to do it, but this is obviously not a nice solution)