Release Notes for JMRI 5.15.5 release

Date: March 13, 2026

From: Bob Jacobsen

Subject: Test Release 5.15.5 of JMRI/DecoderPro is available for download.

Notes:

This is a test release. Please post a note if you encounter any new or old bugs! And please back up your JMRI files before installing this, in case you want to go back to an earlier version.

This is the next in a series of 5.15.* test releases. It requires at least Java 11 to work. We recommend that you use Java 21 if possible. (See our page on downloading Java) We expect this series to result in the next JMRI production release in July 2026. (See the tentative release schedule)

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

Update From Older JMRI Versions

If you are currently using a version older than JMRI 5.0, 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 release.

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, use those from now on, and go on to step 3.
3. Is your current version older than JMRI 4.24? Then update to JMRI 4.24 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.
4. Is your current version older than JMRI 5.0? Then update to JMRI 5.0 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.
5. 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.

New problems with this release

• None yet

New warnings for this release:

• The web server folder app has been removed. It might cause third party applications to fail. If this happens to you, please contact us on the JMRI users group.

Older warnings

See the JMRI 5.14 release note for more warnings predating the 5.15 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 at least JMRI 5.0 before installing this test release. See instructions above.

• Since JMRI 4.99.1 This test release, and all subsequent ones, require the use of Java 11 or later. We recommend that you use Java 21. Java 8 is explicitly not supported. There's more information on this migration on the JMRI Tech Road Map and JVM Capabilities pages.
• If you're using a Firefox web browser and opening JMRI help files locally (not over the web), a Firefox bug can sometimes cause it to enter a loop. There's a workaround in this JMRIusers post.
• Since JMRI 5.15.1 The serial communications library that JMRI uses has been updated. If your JMRI installation is having trouble communicating with your model railroad hardware, please contact us on the JMRI users group.
• Since JMRI 5.15.4 The way mouse clicks are handled has been updated. Although this has been tested with mice and trackpads, it's possible that this will cause problems with other hardware, e.g. touch panels. If you do encounter new problems with clicking on panels, please contact us on the JMRI users list.
Since JMRI 5.15.4
• The RailCom handling has been updated to current standards. In particular, the enum representing the orientation has been changed from ORIENTA and ORIENTB to EAST and WEST respectively and some of the text strings have changed. These may affect any scripts you have that reference the direction of a RailCom report (tag) or parse the status messages.

Download links:

These files are located in the JMRI 5.15.5 GitHub release.

Changes since Test Release 5.15.4:

The full list of included changes is available from our GitHub code repository.

Hardware Support

• Network connections now take their host name/address and port number from the per-node individual configuration, if available, and from the shared configurations if not. This will allow you to have different host name/address for different computers sharing the same JMRI profile.

LocoNet

• Added LNRP3 to some LocoNet Monitor message types.
• Updated the LocoBuffer-USB and LocoBuffer-NG help.

MQTT

• Updated the Signal Mast support so that a mast can be updated by an MQTT message from the layout.

OpenLCB / LCC

• A bug that would cause LCC Reporters to improperly be created as Internal Reporters has been fixed. If you have Internal Reporters that have been created in the past by this bug,
  1. Start this version of JMRI or later
  2. Delete all the IdTags and, if relevant, RailCom tags that reference the internal Reporters
  3. Delete the internal Reporters
  4. Save your panels and table to your usual file
  5. Quit and restart JMRI.
• The OpenLCB_Java library has been updated, which brings
  1. Improvements to how streams are handled, which will make firmware updates to certain node types more reliable.
  2. When opening a configuration ("CDI") window, the window will stay minimized while both the display information (the CDI contents) and the configuration data contents are read. Although this takes longer, it prevents you from accessing data variables that have not yet been loaded. Previously that early access has led to various problems with inconsistent data.
  3. Blank lines are now accepted as comments in node backup files
• The LCC/ChangeDefaultBackupFileName.py script has been updated to include the node's event ID if no node name is available. This will e.g. reduce confusion when backing up brand-new nodes.

Zimo

• Added additional, faster speeds to the KLUG connection.

Control Panel Editor

• Change the scaling menu item from "multiply current scaling" to "set new scaling percentage" form.

DecoderPro

• If multiple roster entries are selected, contextual menu allows opening a throttle window with a controler for each selected roster entries.
• Drag'n drop of roster entries to the throttle list window is now allowed and will create new throttle control in the targetted window.
• Added a new (optional) Permission to control whether the user can edit columns that have been added to the Roster Table. This can be used to e.g. only allow certain people at a club to mark a locomotive entry as having been inspected.
• Added a copy/cut/paste pop-up menu to text fields that didn't previously have a pop-up menu.
• Fixed a bug where certain roster entry contents would cause a crash.

Dispatcher

• Stop train immediately if it has no occupied section, or blocks go active in the wrong order. This behaviour can be turned off in dispatcher options.
• Add the current, next block and train held status to the dispatcher screen.
• When resuming from a failure, inform user where the head of train needs to be or which block needs to be cleared. If they have being using Manual present them with choice about the direction.
• Fix NPE error on dispatcher train restart.
• Fix up to and fro restart at far end

Layout Editor

• Change the scaling menu item from "multiply current scaling" to "set new scaling percentage" form.
• Fixed a problem that could cause bold-text labels to have their contents truncated. e.g. "West" would be shown as "Wes...". This was mostly a problem on Windows, but could have affected any system type.

LccPro

• Added a copy/cut/paste pop-up menu to text fields that didn't previously have a pop-up menu.
• Added "Print Table" and "Export CSV" global buttons that do pretty much what they say.
• Added a "Backup" button to each row that will directly back up the selected node to a file. The directory where that file will be placed can be set with the "Set Backup Directory" action in the Settings menu.

OperationsPro

• Improvements to the print Manifest and no page breaks option.
• New larger preview windows when printing.

Panel Editor

• Change the scaling menu item from "multiply current scaling" to "set new scaling percentage" form.

Roster

• Improved the locomotive image resolution in printed rosters.
• Increased the size of the roster preview so that it matches the paper size and improved text legibility.
• Update "Export Complete Roster" process so that upon "Import Complete Roster" the images will properly display without the need to rebuild the roster.
• The Import Complete Roster action now shows a progress bar.

Throttle

• Throttle list window is now displaying one column for each throttle window, each column showing the throttles for that window
• Throttle list window allows drag'n drop from one window to another
• A throttle preference allows to enable the "ALL" roster group in the roster group seletor of the address panel
• Some interfaces introduced between sing implementation anf throttle controlers

Web Access

• panel.js: handle BlockContentsInputIcon

Web Server

• The web server folder app has been removed. It might cause third party applications to fail. If this happens to you, please contact us on the JMRI users group.

Miscellaneous

• When printing on MacOS, selecting a specific page range to print does not work correctly. This is a known Java issue. The workaround is to print the entire document to PDF, and then use a PDF reader to select the pages to print.
• There's a new option in the Load and Store tab of the Preferences that allows you to exclude storing the contents of memories. Not the configuration of the memories, just their contents. This might be useful if e.g. you're storing your panel&configuration files in a storage system like git that keeps track of changes, and you don't need to track changes in the (transient) memory contents.

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