In lecture 21, talking about duplicating and merging objects, I have a problem ith the periscope challenge.
I have created the shape with 3 objects (two base objects, one duplicate). I moved all of them into the perfect position and then I wanted to join them together, as seen at 08:27 in the video. When I pressed the button, it joined all three objects together, but the top object was changed into a blue-ish faced object, as shown below (image 2). I have no idea what caused this.
(image 1)
(image 2)
I hope someone knows what I did wrong here.