Creating a Jenkins Slave via Java Web Start
Ok, I found it myself!
In the Global Security, I didn't have a TCP port for JNLP agents enabled, which automatically disables the line "Launch agent via Java Web Start"
As mentioned here:
Manage Jenkins => Configure Global Security => Enable security => TCP port for JNLP agentsSet it to either Fixed (for this option also set the port number) or Random.
Manage Jenkins => Configure Global Security => Enable security => TCP port for JNLP agentsSet it to either Fixed (for this option also set the port number) or Random.
As of Jenkins version 2.176.3, there is option enabled when "Launch agent by connecting it to the master" which is same as "launch agent via java web start" once you enable the "Manage Jenkins => Configure Global Security => Agents => TCP port for inbound agents" as mentioned above. e.g. Fixed: 50000