Mysterious "Shape" object

Hi everybody,

I've been using Articulate Storyline's latest version (as of 26.03.2018) and have been doing so for the last 8 months and I've come across a very perplexing issue that I wish to address and see if anyone else has experienced this. Here goes.

Every now and then whenever I insert an object of any type - text, shape or other, I've stumbled upon a mysterious "Shape" object that appears only in my timeline and not on the slide itself. It looks like this:

It doesn't have a description, it overlaps an existing object and is always on the same row as another object - Rectangle 9 in this case. As you can see from the screenshot it takes up space on Rectangle 9's timeline and whenever I try to move, time or delete it I always get the "Send Report" dialog.

I've reported this issue several times but haven't seen a fix for it yet.

Although I sometimes manage to complete my slide regardless, it comes in the way and misclicking it opens up the "Send Report" dialog every time.

Has anyone else seen it? Any idea what may cause this or how to avoid/fix it?