AppCode 2016.3 - Swift Find Usages - Read/Write Filter Doesn't Have Any Effect Follow

Dear JetBrains,

I'm new to AppCode but I have some experience working with other JetBrains toolbox apps. When I use Find Usages feature (which is probably the most frequently used one) and then press on Read/Write filter buttons on the search result it doesn't seem to have any effect.

Is this a bug or the feature is not yet supported?

The code looks like this:

class A {

  private var x: B? {

    didSet { doSomething() }

  } 

}

And I was trying to Find Usages for 'x'.

Also, all the usages seem to be falling under Unclassified Usages category.

Thank you!