Designer Launch Error IllegalAccessError: class

When trying to open a designer session today I get:

I've tried rebooting. This was working yesterday. No updates to anything since then as far as I know. Here is the error in the log file:

Launch failed on step "StartupStep" with error:
java.lang.IllegalAccessError: class de.javasoft.plaf.synthetica.SyntheticaLookAndFeel (in unnamed module @0x4aa36a32) cannot access class sun.swing.DefaultLookup (in module java.desktop) because module java.desktop does not export sun.swing to unnamed module @0x4aa36a32
	at de.javasoft.plaf.synthetica.SyntheticaLookAndFeel.initialize(SyntheticaLookAndFeel.java:840)
	at java.desktop/javax.swing.UIManager.setLookAndFeel(Unknown Source)
	at java.desktop/javax.swing.UIManager.setLookAndFeel(Unknown Source)
	at de.javasoft.plaf.synthetica.SyntheticaLookAndFeel.setLookAndFeelWorkaround(SyntheticaLookAndFeel.java:3767)
	at de.javasoft.plaf.synthetica.SyntheticaLookAndFeel.setLookAndFeel(SyntheticaLookAndFeel.java:3744)
	at com.inductiveautomation.ignition.client.IgnitionLookAndFeel.init(IgnitionLookAndFeel.java:68)
	at com.inductiveautomation.ignition.designer.DesignerStartupHook.staticSetup(DesignerStartupHook.java:199)
	at com.inductiveautomation.ignition.client.launch.steps.StartupStep.run(StartupStep.java:105)
	at com.inductiveautomation.ignition.client.launch.AbstractStepRunner.run(AbstractStepRunner.java:33)
	at java.base/java.lang.Thread.run(Unknown Source)

Probably some AV task killed one of the launch jars. Clear your local cache and try again.