This is a new major release of Namecoin Core. It contains all of the updates
done in upstream
[Bitcoin Core 0.19.0](https://github.com/bitcoin/bitcoin/releases/tag/v0.19.0),
minor improvements to the Namecoin code, and the following Namecoin-specific
user visible change:
The mempool now allows multiple updates of a single name (in a chain of
transactions). This is something that is allowed in blocks already,
i.e. it is just a policy change. The `name_update` RPC command still
prevents such transactions from being created for now, until miners and
relaying nodes have updated sufficiently. More details can be found in
[#322](https://github.com/namecoin/namecoin-core/pull/322).