The auto complete popup of the latest IDE(s) glitches away from the cursor and starts appearing on top of the IDE window, sometimes right of the cursor with large offsets.
After a while it completely disappears until a restart happens.
IDEA Ultimate 2018.3.4 Preview and 2018.3
as well as DataGrip
Not related to EAP only!
it occurs on 3 of our dev PCs