Detected/selected JDK always reported as invalid

The installer correctly detects a JDK but still reports it as invalid. Same goes for selecting an installation of JDK - all checks pass but still the message says the installation is invalid.

It does not seem to be a problem with the detection logic - it returns correct values for me. My guess would be that something is incorrectly propagated to the UI, but I haven't been able to find the source yet.