In my project, in Java files I can Ctrl+Space to get a suggestion to import a value, and can then F12 or Ctrl+LMB to go to it's definition in a decompiled jar.
In Kotlin files, these things are not possible. Auto importing can only be done by typing the name in full and using the quick fix system. Go to definition is simply not available, meaning to view the definition of an external object I must either reference that same object in a java file or manually dig through the referenced libraries to find the correct file.