I think the actual hint here is a reminder that if a site misbehaves, changing the user agent can be an effective troubleshooting tool.] Usually I want to open Gmail in Chrome and URLs pointing to my development server in Firefox. There is this nifty free app called Lin Castor that enables you to register your own handler for an URL.
Although it had beed designed to register your own non-standard URL schemes, it can intercept standard http and https as well.
For Safari, enable the Develop Window and use an option in there that works. [crarko adds: I don't have an older system active at the moment to try this.
It's inevitable that older software becomes obsolete, the same way older hardware does.
The first thing is that you have to do some configuring of both Java and Safari to get the applet to run at all.
For example I have a JIRA app wrapper which looks for anything staring with On two of the Macs, as soon as I fired up the Citrix app, the Java vpn window would show 'error'. Then I remembered that I had done some Java development in the past and installed various jdks from Oracle so I ran: That was on the working Mac.Then I remembered the difference between 'System' Java, Java plugins, and Java development kits.That's why I call it a workaround instead of a fix.I figure Apple is mucking around with Siri and perhaps caused a bug or some sort of corruption.