How to prevent IntelliJ IDEA from deleting unused packages?

Question

I\'m working with intelliJ and my problem is when I start to import some temporary unused packages into my class file intellij delete those line within a second.

how

Answer 1

(Update) For the Scala developers out there, you can have 1/2 the cake and eat the other 1/2 now: disable the auto-optimize for just scala