In 5.5 "Fix imports" used to not only add missing but also remove unused imports. 

With 6.0 this does not happen anymore. As a matter of fact, removing not unused
imports is a lot more complicated than before. 

First you have to scroll to the top of the file (or it's done automatically by
clicking on the orange stripe in the right status bar) 

Then you have to select one of the light bulbs that appear

Then you have to select whether you want to remove only "this" unused import or
all unused imports

A lot of clicking for something that used to happen automatically when doing
"Fix imports"