memo property Null safety
read / write
(deprecated, optional) This field was originally intended to differentiate users of the same Stellar account. However, the anchor should use the sub value included in the decoded SEP-10 JWT instead. Anchors should still support this parameter to maintain support for outdated clients. See the Shared Account Authentication section for more information. https://github.com/stellar/stellar-protocol/blob/master/ecosystem/sep-0024.md#shared-omnibus-or-pooled-accounts
Implementation
String? memo;