id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
20123	"""null"" Preference Tab"	mdk	team	"==== What steps will reproduce the problem?
1. Start JOSM
2. Open Preference Window

==== What is the expected result?
See all the preference tabs.

==== What happens instead?
Before ""Advanced Preferences"" the is a tan called ""null"" which vanish if I click on it. Next time I open the Preference window again, the ""null"" tab apears again.
[[Image(null preference.png)]]

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

{{{
Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2020-11-18 20:16:58 +0100 (Wed, 18 Nov 2020)
Revision:17323
Build-Date:2020-11-19 02:30:51
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (17323 en) Linux Ubuntu 20.10
Memory Usage: 331 MB / 1980 MB (140 MB allocated, but free)
Java version: 14.0.2+12-Ubuntu-1, Private Build, OpenJDK 64-Bit Server VM
Look and Feel: javax.swing.plaf.metal.MetalLookAndFeel
Screen: :0.0 3840x2160 (scaling 1.0x1.0)
Maximum Screen Size: 3840x2160
Best cursor sizes: 16x16 -> 16x16, 32x32 -> 32x32
Desktop environment: ubuntu:GNOME
Java ATK Wrapper package: libatk-wrapper-java:all-0.38.0-1
Environment variable LANG: de_CH.UTF-8
libcommons-compress-java: libcommons-compress-java:all-1.20-1
libcommons-logging-java: libcommons-logging-java:all-1.2-2
fonts-noto: fonts-noto:-
VM arguments: [--add-modules=java.scripting,java.sql, -Djosm.restart=true, -Djosm.dir.name=JOSM-latest, -Djava.net.useSystemProxies=true]

Plugins:
+ ColumbusCSV (35640)
+ FastDraw (35640)
+ HouseNumberTaggingTool (35640)
+ OpeningHoursEditor (35640)
+ RoadSigns (35640)
+ SimplifyArea (35640)
+ buildings_tools (35640)
+ contourmerge (v0.1.6)
+ imagery-xml-bounds (35640)
+ imagery_offset_db (35640)
+ pbf (35640)
+ poly (35640)
+ public_transport (35640)
+ reltoolbox (35640)
+ reverter (35640)
+ terracer (35640)
+ turnrestrictions (35640)
+ utilsplugin2 (35640)
+ wikipedia (1.1.4)

Tagging presets:
+ https://josm.openstreetmap.de/josmfile?page=Presets/OneClick&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Presets/LaneAttributes&preset&zip=1

Map paint styles:
+ https://josm.openstreetmap.de/josmfile?page=Styles/Lane_and_Road_Attributes&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Styles/Maxspeed&style&zip=1
}}}
"	defect	new	normal		Core			template_report