Project Zomboid updates its pre-release branch with integrity checks

Project Zomboid’s pre-release build 42.22.1 adds checks for changes to its Java runtime and fixes an issue with digital-certificate validation. Released on November 4, it is a maintenance update for the testing branch, not an announcement that build 42.22 has become the default stable version.

The hotfix notice names eMudhra certificate validation as the corrected vulnerability. Detected modifications to the Java Runtime Environment are indicated in the version watermark. Third-party license acknowledgements have also been updated. The notice does not identify a new gameplay penalty for that indicator or describe it as a ban notification.

Pre-Release replaces the old Unstable label

The Indie Stone introduced the branch name with the October 27 42.22 announcement. It recommends the default Stable branch for ordinary play and positions Pre-Release as a place for modders, server operators and willing testers to examine upcoming changes.

On Steam, the opt-in is under the game’s Properties, then Game Versions & Betas. Choosing Pre-Release changes which build the client receives. It is not necessary to opt in merely because a new numbered hotfix appears in the news feed.

The intended cycle keeps a build in testing for at least one week before a stable release, with additional revisions when needed. That is a minimum testing period, not an automatic promotion date. The November 4 hotfix is part of that process, so counting seven days from the earlier announcement does not establish that the branch is now stable.

Ladders and crowbars have specific limits

The wider build introduces usable map ladders. The detailed 42.22 notes say they can be used with the default E interaction or through the right-click menu. Zombies cannot climb them, but enemies can still be waiting below when a survivor descends. The ladders are fixed map features; this first implementation is not a general promise of freely placing new ladders wherever needed.

Crowbars can force many locked doors, windows and gates through a contextual action. Success depends on the obstruction, character Strength and the Burglar profession. Repeated failure can damage the tool, and attempts cause Muscle Strain. Security doors and jail-cell doors remain excluded.

That gives the tool a more flexible role without making it a universal key. A weaker survivor facing repeated failures has a different choice from a Burglar opening an ordinary door quietly: keep spending condition and effort, or find another entrance.

Test a copy before moving a long-running world

The broader patch also corrects multiplayer character duplication and moves affected PvP damage calculations to the server. These changes explain why server operators and mod creators are specifically invited to test ahead of a stable rollout; a new client version can matter beyond its visible traversal additions.

The developers expect the hotfix to preserve saves but still ask that reported bugs be reproducible in a fresh, unmodified world. Keep a separate copy of an established save before branch testing. A clean test world helps distinguish a base-game defect from a mod or an older world’s accumulated state, while preserving the campaign intended for ordinary play.