josm-latest crashes on startup: java.security.AccessControlException: access denied ("java.net.SocketPermission" "josm.openstreetmap.de" "resolve")

[matthijs]

Since today, josm-latest (16976) crashes on startup. Yesterdays version (16952 IIRC, at least 5something) still worked. The first time I started today, I got asked to update plugins and I did that, so maybe the cause is there. At startup, I get the following:

​https://i.imgur.com/27u56Eb.png

Note that I can't click the "Report bug" button, since the other dialog is modal (so I don't have the nice and prefilled bug report template here, since I can't access that option).

When I click "Show Details", I get:

net.sourceforge.jnlp.LaunchException: Fatal: Launch Error: Could not launch JNLP file. The application has not been initialized, for more information execute javaws/browser from the command line and send a bug report.
	at net.sourceforge.jnlp.Launcher.launchApplication(Launcher.java:582)
	at net.sourceforge.jnlp.Launcher$TgThread.run(Launcher.java:945)
Caused by: java.lang.reflect.InvocationTargetException
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at net.sourceforge.jnlp.Launcher.launchApplication(Launcher.java:576)
	... 1 more
Caused by: org.openstreetmap.josm.tools.JosmRuntimeException: java.util.concurrent.ExecutionException: java.security.AccessControlException: access denied ("java.net.SocketPermission" "josm.openstreetmap.de" "resolve")
	at org.openstreetmap.josm.spi.lifecycle.Lifecycle.initialize(Lifecycle.java:81)
	at org.openstreetmap.josm.gui.MainApplication.mainJOSM(MainApplication.java:919)
	at org.openstreetmap.josm.gui.MainApplication$3.processArguments(MainApplication.java:277)
	at org.openstreetmap.josm.gui.MainApplication.main(MainApplication.java:714)
	... 6 more
Caused by: java.util.concurrent.ExecutionException: java.security.AccessControlException: access denied ("java.net.SocketPermission" "josm.openstreetmap.de" "resolve")
	at java.base/java.util.concurrent.ForkJoinTask.get(ForkJoinTask.java:1006)
	at org.openstreetmap.josm.spi.lifecycle.Lifecycle.initialize(Lifecycle.java:75)
	... 9 more
Caused by: java.security.AccessControlException: access denied ("java.net.SocketPermission" "josm.openstreetmap.de" "resolve")
	at java.base/java.security.AccessControlContext.checkPermission(AccessControlContext.java:472)
	at java.base/java.security.AccessController.checkPermission(AccessController.java:897)
	at java.base/java.lang.SecurityManager.checkPermission(SecurityManager.java:322)
	at net.sourceforge.jnlp.runtime.JNLPSecurityManager.checkPermission(JNLPSecurityManager.java:292)
	at java.base/java.lang.SecurityManager.checkConnect(SecurityManager.java:821)
	at java.base/sun.net.www.protocol.jar.JarFileFactory.getCachedJarFile(JarFileFactory.java:141)
	at java.base/sun.net.www.protocol.jar.JarFileFactory.get(JarFileFactory.java:81)
	at java.base/sun.net.www.protocol.jar.JarURLConnection.connect(JarURLConnection.java:125)
	at java.base/sun.net.www.protocol.jar.JarURLConnection.getInputStream(JarURLConnection.java:155)
	at java.base/java.net.URLClassLoader.getResourceAsStream(URLClassLoader.java:328)
	at org.openstreetmap.josm.tools.Utils.getResourceAsStream(Utils.java:1881)
	at org.openstreetmap.josm.tools.ResourceProvider.lambda$getResourceAsStream$1(ResourceProvider.java:83)
	at org.openstreetmap.josm.tools.ResourceProvider.getFirstNotNull(ResourceProvider.java:58)
	at org.openstreetmap.josm.tools.ResourceProvider.getResourceAsStream(ResourceProvider.java:83)
	at org.openstreetmap.josm.io.CachedFile.getInputStream(CachedFile.java:230)
	at org.openstreetmap.josm.tools.Territories.initializeInternalData(Territories.java:136)
	at org.openstreetmap.josm.tools.Territories.initialize(Territories.java:123)
	at org.openstreetmap.josm.gui.MainInitialization.lambda$parallelInitializationTasks$6(MainInitialization.java:114)
	at org.openstreetmap.josm.spi.lifecycle.InitializationTask.call(InitializationTask.java:33)
	at org.openstreetmap.josm.spi.lifecycle.InitializationTask.call(InitializationTask.java:11)
	at java.base/java.util.concurrent.ForkJoinTask$AdaptedCallable.exec(ForkJoinTask.java:1448)
	at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290)
	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1020)
	at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1656)
	at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1594)
	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183)

It looks like there is some permission error on resolving josm.openstreetmap.de, but I can't quite understand why this is a problem now and not yesterday. Any suggestion about where such permissions are controlled?