Drag and Drop issue using Firefox

I made a quiz site for kids. It contains only images and dropzones.
The problem is when i want to move an image to the dropzone i need to click twice.
With Google Chrome it works fine.

A video about the problem: https://drive.google.com/open?id=19mMOS4K8Tgd_PC9zbg7kav7I5SOLxiLJ

Excuse my English!

BV52's picture

Hi S_Sandor,

Thank you for reprting this. I filed a bug report and you can follow the progress here.