The problem fixed by JDK-8307091 seems to be occurring again:

java.util.ConcurrentModificationException
at java.base/java.util.AbstractList$SubList.checkForComodification(AbstractList.java:906)
at java.base/java.util.AbstractList$SubList.size(AbstractList.java:792)
at java.base/java.util.AbstractCollection.toArray(AbstractCollection.java:143)
at java.base/java.util.Collections$SynchronizedCollection.toArray(Collections.java:2311)
at java.base/java.util.Vector.<init>(Vector.java:182)
at java.desktop/javax.swing.plaf.basic.BasicDirectoryModel$FilesLoader$1.call(BasicDirectoryModel.java:365)
at java.desktop/javax.swing.plaf.basic.BasicDirectoryModel$FilesLoader$1.call(BasicDirectoryModel.java:342)
at java.desktop/sun.awt.shell.ShellFolderManager$DirectInvoker.invoke(ShellFolderManager.java:148)
at java.desktop/sun.awt.shell.ShellFolder.invoke(ShellFolder.java:532)
at java.desktop/sun.awt.shell.ShellFolder.invoke(ShellFolder.java:518)
at java.desktop/javax.swing.plaf.basic.BasicDirectoryModel$FilesLoader.run0(BasicDirectoryModel.java:342)
at java.desktop/javax.swing.plaf.basic.BasicDirectoryModel$FilesLoader.run(BasicDirectoryModel.java:295)
at java.base/java.lang.Thread.run(Thread.java:1570)