All categories are folded by default

[bagage]

What steps will reproduce the problem?

1. Open josm, download some OSM data
2. Launch validator

What is the expected result?

Warnings/errors are displayed, stored by categories. You can review them quickly.

What happens instead?

Warnings/errors are generated, but these 2 panels (error/warning) are folded. So you cannot see all categories easily, you have to click on error/warning. Then next validator action will leave it open.

I don't see the value of folding error/warning categories at start, because by itself it's not very useful I believe.
But even better, I'd like if JOSM could save my preferences on which categories (Crossing highways, …) I opened, so that next time I open JOSM, it will open these directly without me having to click.

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: 2018-12-31 15:09:58 +0100 (Mon, 31 Dec 2018)
Build-Date:2018-12-31 14:24:10
Revision:14620
Relative:URL: ^/trunk

Identification: JOSM/1.5 (14620 fr) Linux Debian GNU/Linux buster/sid
Memory Usage: 1127 MB / 4436 MB (804 MB allocated, but free)
Java version: 1.8.0_191-8u191-b12-2-b12, Oracle Corporation, OpenJDK 64-Bit Server VM
Screen: :0.0 1920x1080
Maximum Screen Size: 1920x1080
Java package: openjdk-8-jre:amd64-8u191-b12-2
Java ATK Wrapper package: libatk-wrapper-java:all-0.33.3-21
Dataset consistency test: No problems found

Plugins:
+ AddrInterpolation (34867)
+ HouseNumberTaggingTool (34867)
+ OpeningHoursEditor (34867)
+ PicLayer (34867)
+ apache-commons (34506)
+ buildings_tools (34867)
+ conflation (0.6.2)
+ ejml (34389)
+ geojson (116)
+ geotools (34513)
+ jts (34524)
+ poly (34867)
+ scripting (30794)
+ terracer (34867)
+ todo (30306)
+ utilsplugin2 (34867)

Last errors/warnings:
- W: No configuration settings found.  Using hardcoded default values for all pools.