Segregated Witness (SegWit) moves the proof of ownership from the scriptSig part of the transaction to a new part called the witness of the input. Before SegWit the transaction signature was used in the calculation of the transaction id. The signature contains the same information as a P2PKH spend but is located in the witness instead of the scriptSig. The scriptPubKey is modified from
scriptPubKey: OP_DUP OP_HASH160 <pubKeyHash> OP_EQUALVERIFY OP_CHECKSIG
scriptPubKey: O <pubKeyHash>
P2WPKH in Trezor and Trezor Wallet
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