You can select different JRE in EJS if you have more than one version installed.
In the past, it only affect EJS. EJS will use selected JRE to run itself and generated simulation.
However, java process did not kill itself when EJS or any java application finished, now.
The java console is always there once java has been activated.
I am not sure how it will affect your browser in MAC.
But I can select which JRE to use be used from java control panel (Right click java console icon) in Window system.