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Release Notes for JMRI 4.26 release

Date: December 16, 2021

From: Bob Jacobsen

Subject: Production Release 4.26 of JMRI/DecoderPro is available for download.

We are very pleased to announce that the 4.25 series of JMRI test releases has resulted in a version that's good enough to be recommended for general use, including by new users. We're therefore making that version, "Production Release 4.26" available for download today.

Notes:

JMRI is now only available under the GNU General Public License. For more information, please see our copyright and licensing page.

This is the last JMRI production or test version that will work with Java 1.8.
To use any future JMRI test or production releases, you'll have to update the Java on your computer to Java 11. See our page on downloading Java 11. This version has been tested on Java 11, so you can do the Java update now if you want to.

Update From Older JMRI Versions

If you are currently using a version older than JMRI 4.20, please follow these instructions carefully:
  1. Is your current version older than JMRI 4.12? If so, then update to JMRI 4.12 first, and ensure everything works correctly: check start-up, check things you need to be working, and check the JMRI log as well) before doing anything else. Store your configuration and panel files under a new name and use those from now on. Then continue with step 2.

    If you are currently using JMRI 4.7.3 or earlier on Linux or macOS (Windows doesn't need this), then it's very important that you update to JMRI 4.12 and carrying out the migration process described in the JMRI 4.12 release note before updating to any later relese.

  2. Is your current version older than JMRI 4.20? Then update to JMRI 4.20 first, and ensure that works correctly (check start-up, check things you need to be working, and check the JMRI log as well) before doing anything else. Save your preferences again. Store your configuration and panel files under a new name and use those from now on.
  3. You can then install this release.
Following this multi-step order of updating via stable major releases safeguards you against possible migration issues that can arise from skipping these versions.

Known problems with this release

New warnings for this release:

Older warnings

See the JMRI 4.20 release note for more warnings predating the 4.21 development series, including pointers to various migration issues. These may be relevant to you if you're updating from an earlier version; we strongly recommend you update to JMRI 4.20 before installing this release.

Download links:

Changes since production release 4.24:

This production version is made from test releases 4.25.1 through 4.25.9 The full list of changes in those is available from our code repository.

Hardware Support

CBUS

DCC++ and DCC-EX

LocoNet

MERG

MQTT

SPROG

New / Updated decoder definitions

Doehler & Haas

LDH

SoundTraxx

TAMS

DecoderPro

LogixNG

Operations

Panel Editor

Control Panel Editor

Palette

Scripting

Signals

Signal Systems

Signal Masts

USS CTC Logic

Throttle

Transits

Turnouts, Lights, Sensors and other elements

Warrants

Miscellaneous