Answer
This is a known OpenJDK bug in the AWT/window-initialization code, affecting the JDK 14 version bundled with Developer Studio at this release, and it's fixed starting in a later JDK version (16) that Developer Studio doesn't yet ship with. Until Developer Studio is updated to a newer bundled JDK where this is fixed, the practical workaround is switching the Windows OS language to English instead of the affected non-English locale — this avoids triggering the specific AWT code path that crashes. If you're stuck needing the non-English locale for other reasons, this is worth reporting to IFS R&D as a request to update the bundled JDK version.