its seems to be that this version is needed (and 2.24 is broken in combination with Jenkins 0.289.3):
vsphere-cloud:2.26

else you will be unable to create/clone/edit job configurations.
instead only the save button will stay highlighted forever and on next click to e.g. Dashboard you will get asked for leaving the page because of still unsaved content. (seems the web interface saving stalls under the hood.)