Ah, I should probably watch these forums more often. I’ve got netbeans and intellij installed and wondered why I had conflicts when updating.
My fix: I removed netbeans and intellig, then both the JRE and JDK. I then Installed the new JDK (I think mine was v17 before the updates), then netbeans and intellij. All is working fine. To be honest, I always thought the dev kit contained the runtime anyway? It used to anyway (back in my Windows days 
)…