Session Custom Variable 1-3 not sent (platform, OS, app version)

[fl034]

I'm using iOS and Android SDKs. For iOS the variables 1-3 are filled with platform, OS version and app version as default.

In Android, it's not working. Sending application download event works.

Tested with 2.0.0.

Documentation states it is on by default: https://developers.piwik.pro/docs/setincludedefaultcustomvars

The setIncludeDefaultCustomVars() method turns on or off fetching platform, OS and app version from the tracker instance. It is turned on by default.
If setIncludeDefaultCustomVars(true) is set, indexes 1-3 are used to track the platform, OS and app version as custom variables.

Here's my code

class MyApplication : PiwikApplication() {
    override fun onCreate() {
        super.onCreate()
        enableMainActivity()
        tracker.setAnonymizationState(true)
        if (!BuildConfig.DEBUG) {
            TrackHelper.track().sendApplicationDownload().with(tracker)
            tracker.dryRunTarget = null
        } else {
            tracker.dryRunTarget = emptyList()
        }
    }
   
    ...
}