Conflict resolution box sometimes freezes

[chris@…]

What steps will reproduce the problem?

1. Have a conflict in your changeset (either on upload or download)
2. Open the conflict resolution box
3. Click around a bit

What is the expected result?

The selected "correct" tag goes into the middle column

What happens instead?

JOSM freezes

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

This might be some sort of Java on Mac stuff or maybe networking? It's a good thing JOSM can usually restore from a crash. Also, the debug data might be junk, since I clicked the submit bug button before triggering the freeze.

URL:http://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2017-12-31 03:09:43 +0100 (Sun, 31 Dec 2017)
Build-Date:2017-12-31 02:33:46
Revision:13265
Relative:URL: ^/trunk

Identification: JOSM/1.5 (13265 en) Mac OS X 10.11.6
OS Build number: Mac OS X 10.11.6 (15G18013)
Memory Usage: 696 MB / 1820 MB (432 MB allocated, but free)
Java version: 1.8.0_161-b12, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
Screen: Display 2026427093 1920x1080
Maximum Screen Size: 1920x1080
VM arguments: [-Djava.security.policy=file:<java.home>/lib/security/javaws.policy, -DtrustProxy=true, -Djnlpx.home=<java.home>/bin, -Djava.security.manager, -Djnlpx.origFilenameArg=${HOME}/Library/Application Support/Oracle/Java/Deployment/cache/6.0/56/1ee8cfb8-668392a0, -Djnlpx.remove=false, -Dsun.awt.warmup=true, -Djava.util.Arrays.useLegacyMergeSort=true, -Dmacosx.jnlpx.dock.name=JOSM, -Dmacosx.jnlpx.dock.icon=${HOME}/Library/Application Support/Oracle/Java/Deployment/cache/6.0/16/47ee53d0-5050928a.icns, -Djnlp.application.href=https://josm.openstreetmap.de/download/josm.jnlp , -Djnlpx.jvm="<java.home>/bin/java"]
Dataset consistency test: No problems found

Last errors/warnings:
- W: No configuration settings found.  Using hardcoded default values for all pools.
- W: Region [TMS_BLOCK_v2] Resetting cache