imported images disappear after action

Hello,
I'm starting to use LibreCAD after experimenting AutoCAD at my office. I have some trouble with importing images.
Image import works but when I do action on images (scale, move, rotate...) they are no more displayed. I found a trick with save then open the same file. They are displayed again.
How can I manage to improve that? The image quality (dpi, size pixel), its format (.jpg, .png...) are important?
Thanks for your help.
Cheers

Version : 2.1.2
Compiler: GNU GCC 6.2.0
Compilé sur : Sep 17 2016
Qt Version: 5.9.5
Boost Version: 1.62.0
System: Linux Mint 19

This is a bug. Just do an AutoZoom and the image is back.
The issue has been fixed in the 2.2.0 RC version.

Ho thanks! You save my day.