I only had this:
implementation "org.jmonkeyengine:jme3-lwjgl3:$jmeVersion"
because it was enough with 3.5.2.
Adding the jme3-desktop solved that but now I get:
gen 12, 2023 2:45:20 PM com.jme3.app.LegacyApplication handleError
GRAVE: Uncaught exception thrown in Thread[jME3 Main,5,main]
java.lang.NoSuchMethodError: java.nio.ByteBuffer.clear()Ljava/nio/ByteBuffer;
at com.jme3.util.BufferUtils.createByteBuffer(BufferUtils.java:996)
at com.jme3.system.lwjgl.LwjglWindow.imageToGLFWImage(LwjglWindow.java:400)
at com.jme3.system.lwjgl.LwjglWindow.imagesToGLFWImages(LwjglWindow.java:375)
at com.jme3.system.lwjgl.LwjglWindow.setWindowIcon(LwjglWindow.java:353)
at com.jme3.system.lwjgl.LwjglWindow.createContext(LwjglWindow.java:294)
at com.jme3.system.lwjgl.LwjglWindow.initInThread(LwjglWindow.java:501)
at com.jme3.system.lwjgl.LwjglWindow.run(LwjglWindow.java:619)
at com.jme3.system.lwjgl.LwjglWindow.create(LwjglWindow.java:473)
at com.jme3.app.LegacyApplication.start(LegacyApplication.java:490)
at com.jme3.app.LegacyApplication.start(LegacyApplication.java:442)
at com.jme3.app.SimpleApplication.start(SimpleApplication.java:126)
Java 8 btw!