NPE in Relation editor dialog after creating a copy of a relation

[josm@…]

What steps will reproduce the problem?

1. Click on a relation in the relations panel
2. Click the create a copy of this relation and open it in another editor window button

What is the expected result?

Can edit relation

What happens instead?

JOSM has crashed box appears

Please provide any additional information below. Attach a screenshot if possible.

URL:https://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2018-03-04 16:20:37 +0100 (Sun, 04 Mar 2018)
Build-Date:2018-03-04 15:24:13
Revision:13500
Redirecting:to URL 'https://josm.openstreetmap.de/svn/trunk':
Relative:URL: ^/trunk

Identification: JOSM/1.5 (13500 en_GB) Linux Ubuntu 17.10
Memory Usage: 506 MB / 1292 MB (344 MB allocated, but free)
Java version: 1.8.0_151-8u151-b12-0ubuntu0.17.10.2-b12, Oracle Corporation, OpenJDK 64-Bit Server VM
Screen: :0.0 1920x1080
Maximum Screen Size: 1920x1080
Java package: openjdk-8-jre:amd64-8u151-b12-0ubuntu0.17.10.2
Java ATK Wrapper package: libatk-wrapper-java:all-0.33.3-13
VM arguments: [-Djosm.restart=true, -Djava.net.useSystemProxies=true]
Dataset consistency test: No problems found

Plugins:
+ reverter (34036)
+ terracer (33839)
+ undelete (33980)
+ utilsplugin2 (33991)

Last errors/warnings:
- W: No configuration settings found.  Using hardcoded default values for all pools.
- E: Handled by bug report queue: java.lang.NullPointerException


=== REPORTED CRASH DATA ===
BugReportExceptionHandler#handleException:
No data collected.

Warning issued by: BugReportExceptionHandler#handleException

=== STACK TRACE ===
Thread: AWT-EventQueue-1 (18) of main
java.lang.NullPointerException
	at org.openstreetmap.josm.gui.dialogs.relation.actions.AbstractRelationEditorAction.canDownload(AbstractRelationEditorAction.java:57)
	at org.openstreetmap.josm.gui.dialogs.relation.actions.DownloadIncompleteMembersAction.updateEnabledState(DownloadIncompleteMembersAction.java:60)
	at org.openstreetmap.josm.gui.dialogs.relation.actions.DownloadIncompleteMembersAction.<init>(DownloadIncompleteMembersAction.java:43)
	at org.openstreetmap.josm.gui.dialogs.relation.GenericRelationEditor$LeftButtonToolbar.<init>(GenericRelationEditor.java:667)
	at org.openstreetmap.josm.gui.dialogs.relation.GenericRelationEditor.<init>(GenericRelationEditor.java:223)
	at org.openstreetmap.josm.gui.dialogs.relation.RelationEditor.getEditor(RelationEditor.java:116)
	at org.openstreetmap.josm.actions.relation.DuplicateRelationAction.duplicateRelationAndLaunchEditor(DuplicateRelationAction.java:35)
	at org.openstreetmap.josm.actions.relation.DuplicateRelationAction.actionPerformed(DuplicateRelationAction.java:48)
	at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
	at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2348)
	at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
	at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
	at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
	at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:289)
	at java.awt.Component.processMouseEvent(Component.java:6533)
	at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
	at java.awt.Component.processEvent(Component.java:6298)
	at java.awt.Container.processEvent(Container.java:2236)
	at java.awt.Component.dispatchEventImpl(Component.java:4889)
	at java.awt.Container.dispatchEventImpl(Container.java:2294)
	at java.awt.Component.dispatchEvent(Component.java:4711)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4888)
	at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4525)
	at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4466)
	at java.awt.Container.dispatchEventImpl(Container.java:2280)
	at java.awt.Window.dispatchEventImpl(Window.java:2746)
	at java.awt.Component.dispatchEvent(Component.java:4711)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
	at java.awt.EventQueue.access$500(EventQueue.java:97)
	at java.awt.EventQueue$3.run(EventQueue.java:709)
	at java.awt.EventQueue$3.run(EventQueue.java:703)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:90)
	at java.awt.EventQueue$4.run(EventQueue.java:731)
	at java.awt.EventQueue$4.run(EventQueue.java:729)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
	at org.GNOME.Accessibility.AtkWrapper$5.dispatchEvent(AtkWrapper.java:700)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

[josm@…]

Screenshot directly after clicking the button. Relation editor never opens

[Don-vip]

In 13509/josm:

fix #16060 - NPE + minor fixes

[Don-vip]

Ticket #16079 has been marked as a duplicate of this ticket.

[Don-vip]

Ticket #16083 has been marked as a duplicate of this ticket.

[Don-vip]

Ticket #16099 has been marked as a duplicate of this ticket.

[Don-vip]

Ticket #16114 has been marked as a duplicate of this ticket.

[Don-vip]

Ticket #16116 has been marked as a duplicate of this ticket.

[Klumbumbus]

Ticket #16125 has been marked as a duplicate of this ticket.