Please read the release notes at https://github.com/JoinMarket-Org/joinmarket-clientserver/blob/master/docs/release-notes/release-notes-0.9.5.md for details on what this release includes.
The bulk of the changes in this release were fixes and improvements to the RPC API (which is now documented here ), done with the help and testing of contributors to the new web UI project here, a particular shout out to theborakompanioni and dennisreimann, but also many others helped out with reports and suggestions. Note that "fully functional" certainly does not mean either complete, nor bug-free! More work is needed.
The other major change is based on the upgrade to our Bitcoin backend, work done by dgpv - it now supports bech32m so we also now support sending (via any of our interfaces) to taproot (segwit v1) addresses. (Note that python-bitcointx now has full taproot support in its master branch; active review would be welcome there).
Other changes are mostly smaller improvements, fixes, but as usual, you are very strongly recommended to upgrade as soon as possible.
A windows binary (.exe) is provided, as usual.