Please can you give more details like the system you use to render e.g. Mecabricks online render mode, blender, etc.
Please also provide an image to show what you observe .
I highly doubt that this post shall be in the bug section. Help shall be more appropriate.

How do I get a picture into my reply?

You need to use an external image storage like imgur or flickr or any else, and just paste the BBcode.

Example from imgur.com