Objects created on ProBuilder are disappearing from scene since Unity update, what's going on?

Hi Unity folk

Since upgrading to the latest Unity 2019.1.5f1 I’ve encountered strange issues with ProBuilder. The walls, doors, windows and general structures I’ve created in ProBuilder now seem unstable. Many have disappeared from the scene view (also in play mode) and continue to disappear as I edit the scene. Their object is still in the Hierarchy and has not been unchecked in scene view, in the inspector everything still comes up however it has a note saying “Lightmap UV’s are missing, please Generate Lightmap UV’s” but when I press the button “Generate Lightmap UV’s” nothing happens. The ‘Object Size (read only)’ has also been wiped and is back to 0,0,0

I’ve attached two screen shots to show what happens when I edit simple window objects created on ProBuilder. Screenshot 1 is before copy and paste attempt, screen shot 2.1 is after and shows what is in the inspector (also you can see how a third window has disappeared too!)

I’ve tried uninstalling and then re-installing Pro Builder but with no luck. Please help!

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I’ve been having the same issue and I don’t know how to solve it.