Error on pasting element in Expression binding

Ignition
1

Hello,

I receive this error when I paste a reference to root.custom.prop.

This is the expression binding:
concat('New Value: ', {/root.custom.data_out.di_5})

All I am doing is pasting in a new reference like: {/root.custom.data_out.user} to replace the existing one. (No, I am not pasting this exact reference...)

And the error I get in the console: (Twice)

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$a.actionPerformed(Unknown Source)
	at java.desktop/javax.swing.Timer.fireActionPerformed(Unknown Source)
	at java.desktop/javax.swing.Timer$DoPostEvent.run(Unknown 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$4.run(Unknown Source)
	at java.desktop/java.awt.EventQueue$4.run(Unknown Source)
	at java.base/java.security.AccessController.doPrivileged(Unknown Source)
	at java.base/java.security.ProtectionDomain$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/java.awt.EventDispatchThread.run(Unknown Source)

UPDATE:
Now, I only get this error message every time I type in the expression area:

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException