Preferences don't always save (OS X)

[anonymous]

What steps will reproduce the problem?

1. Open preferences
2. Change something (Eg. in display of GPX track)
3. Press OK

What is the expected result?

Preferences should save, window should close.

What happens instead?

On pressing ok, changed settings revert to previous values. Window doesn't close.

This seems to occur work as follows:

1. The first Ok click reverts - or if you dont change anything, the first ok click does NOT close the window
2. the making changes (or making changes again), and
3. clicking ok again, closes the window as expected.

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

Also tested wth latest version 10786.

URL:http://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2016-06-04 17:28:58 +0200 (Sat, 04 Jun 2016)
Build-Date:2016-06-04 15:31:27
Revision:10327
Relative:URL: ^/trunk

Identification: JOSM/1.5 (10327 en) Mac OS X 10.11.6
Memory Usage: 641 MB / 910 MB (228 MB allocated, but free)
Java version: 1.8.0_101-b13, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
VM arguments: [-Djava.library.path=/Applications/JOSM.app/Contents/MacOS, -DLibraryDirectory=${HOME}/Library, -DDocumentsDirectory=${HOME}/Documents, -DApplicationSupportDirectory=${HOME}/Library/Application Support, -DCachesDirectory=${HOME}/Library/Caches, -DSandboxEnabled=false, -Dapple.laf.useScreenMenuBar=true, -Dcom.apple.macos.use-file-dialog-packages=true, -Dcom.apple.macos.useScreenMenuBar=true, -Dcom.apple.mrj.application.apple.menu.about.name=JOSM, -Dcom.apple.smallTabs=true]
Dataset consistency test: No problems found

Plugins:
- buildings_tools (32309)
- editgpx (32485)
- gpxfilter (32309)
- imagery_offset_db (32329)
- reverter (32584)
- undelete (32584)
- utilsplugin2 (32158)

Last errors/warnings:
- W: Cannot start IPv6 remotecontrol https server on port 8112: Keystore was tampered with, or password was incorrect