From HandWiki

Run "Java Control Panel". Then add "" to the "Exception site list" in the Security tab. This should look as this (for Java8):


Then restart the browser.

When you look at the tutorial sections for each topic, the browser downloads the needed jar files. This will take 5 seconds depending on the network. The you will see the message:


Click "Accept" and press "Run".

See additional help:

One can test your Java settings using this Java powered link.