The icon under cursor isn't jumping. Actually the icon deforms like it's jumping but does not move at all(does not change its vertical position).
On mouse click the icon moves a bit (I mean vertical position).
In 4.8.4 everything was fine with cursor.
I am using 4.9.00 packages from kubuntu-backports repository at the moment.
*** This bug has been marked as a duplicate of bug 304253 ***