Why does the dependency line in Plans doesn't follow the mouse pointer ?

[Andrei Eleodor Sirbu]

Hello community, 

I've noticed that whenever I try to drag a dependency line in a plan, Jira only displays a horizontal gray line.

If I move my pointer around the line doesn't move - you can see it in the screenshot next to the purple bar

At first I thought it happens only when issues are grouped in a plan but it doesn't. 

Does anyone else have this problem ?

Thanks for your help