prevent import optimizing when copy/paste file

Hi,
can you point me to setting, which would prevent optimizing imports after copy pasting file in project tree? I've checked, that optimizing imports on the fly is disabled, inserting imports on paste as well. 
 

My code is as follows

fun main() {
    // do something
          testInput()
}

private fun testInput() {
    System.setIn(java.io.ByteArrayInputStream("abc".toByteArray()))
}

After copying and pasting the file, java.io.ByteArrayInputStream gets extracted to import section. 
 

Thanks,
Kamil