Change Details

Backport of https://github.com/spesmilo/electrum/commit/a88a2dea8255532abdd20002c866b443237a509c Depends on D16278

Backport of https://github.com/spesmilo/electrum/commit/a88a2dea8255532abdd20002c866b443237a509c Also remove unused function `xpub_from_pubkey` Depends on D16278

Backport of https://github.com/spesmilo/electrum/commit/a88a2dea8255532abdd20002c866b443237a509c Also remove unused function `xpub_from_pubkey` Depends on D16278