(J)Wt 4.12.1 is a bigger patch release that fixes a couple of issues, and also introduces some improvements. Check the release notes for more info.
The main points of attention are:
some improvements for bot handling and detection
fixed an erroneous configuration option introduced in 4.12.0
fixes and improvement to styling
Here are the links:
Wt 4.12.1 (C++): download wt-4.12.1.tar.gz (release notes)
JWt 4.12.1 (Java): download jwt-4.12.1.zip (release notes)
Binary builds for Windows are available on the GitHub releases page.