Massive Errors in Console

I just noticed that I'm getting the following error in the console, it seems to spam a dozen of the same thing every couple of minutes.

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException: Cannot invoke "com.jidesoft.editor.SyntaxDocument.getLength()" because "this._document" is null
	at com.jidesoft.editor.CodeEditor.offsetToModelPosition(Unknown Source)
	at com.jidesoft.editor.CodeEditor.offsetToViewPosition(Unknown Source)
	at com.jidesoft.editor.CodeEditorPainter.invalidateRange(Unknown Source)
	at com.jidesoft.editor.CodeEditorPainter.invalidateSelectedLines(Unknown Source)
	at com.jidesoft.editor.CodeEditor.blinkCaret(Unknown Source)
	at com.jidesoft.editor.action.InputHandler$a.actionPerformed(Unknown Source)
	at java.desktop/javax.swing.Timer.fireActionPerformed(Unknown Source)
	at java.desktop/javax.swing.Timer$ Source)
	at java.desktop/java.awt.event.InvocationEvent.dispatch(Unknown Source)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.desktop/java.awt.EventQueue$ Source)
	at java.desktop/java.awt.EventQueue$ Source)
	at java.base/ Source)
	at java.base/$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.desktop/java.awt.EventQueue.dispatchEvent(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.desktop/ Source)

I have no idea where to start here, except for a few random threads but none seem to have the this._document is null issue.

Edit: the Gateway logs show no indication of a problem.

Restart the Designer?
An expression or SQL editor field somewhere in the designer is in an invalid state. Most likely there was a root cause error that's long since lost under the flood of other messages.
If it's happening consistently, then trying to figure out how to trigger it and sending that info to support would be much appreciated. If it's a random unicorn cosmic ray kind of bug that goes away when you restart the Designer, probably not much to do.