Ubuntu 18.04 - MATLAB 2019b fails to open Property Inspector for custom class

I have written a bunch of custom MATLAB classes and everything works smoothly on Windows 10.

However, I recently installed MATLAB in Ubuntu 18.04 and whenever I try to open the property inspector for an instance of the custom classes, the Property Inspector never opens and I get the following error:

Exception in thread "AWT-EventQueue-0": java.lang.NullPointerException
	at com.mathworks.page.plottool.propertyinspectormanager.PropertyInspectorManager$2.run(PropertyInspectorManager.java:167)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
	at java.awt.EventQueue.access$500(EventQueue.java:97)
	at java.awt.EventQueue$3.run(EventQueue.java:709)
	at java.awt.EventQueue$3.run(EventQueue.java:703)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

In addition, upon starting matlab, the following printout is displayed in the Terminal, which may or may not have anything to do with the above,

Gtk-Message: 00:07:13.004: Failed to load module "canberra-gtk-module"
[1024/000717.078965:INFO:context.cpp(159)] Using multi-threaded message loop for Linux

GLib-GIO-Message: 00:07:17.214: Using the 'memory' GSettings backend.  Your settings will not be saved or shared with other applications.

Any help would be highly appreciated.

UPDATE:

I uninstalled R2019b and installed R2019a and now both the Property Inspector work normally, plus I no longer get the second set of "error" printouts when MATLAB starts.

[Aradhana Singh]

I have installed R2019a, and for that also getting the same error, is there any other solution?

[Jack Kenney]

The workaround steps in this Bug Report may fix the issue with the second set of printouts:

https://www.mathworks.com/support/bugreports/details/1995075#fix_options