In JBIDE-24584 I requested that cdk server adapter be renamed to cdk 2 which is now done. But today I noticed that we missed the runtime detector:
Go to Preferences -> JBoss Tools -> JBoss Runtime Detection
On that page, there is a table called Available runtime detectors which, among others, includes:
Container Development Environment 3
Container Development Environment

So the latter should be renamed to include "2" or "2.x" - probably the latter to be consistent with the server adapter name.