使用 firefox 浏览器打开console时，如果是Java plugin的话，经常回报error click for details 。如果查看details会有

Your security settings have blocked an untrusted application from
running.

这不是firefox的问题，而是Java 设置问题。解决方法如下：

You need to change the settings in your Java Control Panel. To do
this: 1) click the apple logo in the top left hand corner of the
computer screen, then click system preferences 2) Find and double
click on the Java logo. The Java Control Panel should open. If it
doesn't, click "Reopen the Java Control Panel" 3) In the Java Control
Panel, click the "Security" tab. 4) Click "Edit site list" and add the
address of the site that is blocked. Click Okay. 5) Click Okay again
and try to access your streaming quote applet.

If this doesn't work, go back into the "Security" tab in the Java
Control Panel and drag the "Security Level" bar to Medium. This will
allow you to access your streaming quotes until you figure out how to
add the site exception.

通过HP服务器的 Integrated Lights-Out (ILO) 连接远程桌面时会报Java 错误Class Not Found等，如图

这是由于在 JDK 7 和 JDK 8 中默认使用 TLS 连接，而 ILO 仅支持 TLS 1.0 的原因。解决方法如下：

1. 打开 Java Control Panel；（ubuntu 在JAVA_HOME/bin/ControlPanel）
2. 在 Advance Tab下勾掉 TLS 1.1 和 TLS 1.2 ；
3. 重新登录即可。