So, today MU 'reposted' this HP PRinter Driver 5.1 update, rebranding it with a December 27, 2018 date. This update was released by Apple on October 24, 2017 (2017, not 2018), making it over a year old. Don't believe me? Here's the link:https://support.apple.com/kb/DL1888?viewlocale=en_US&locale=en_USSo, does MU know this update is 14 months old and decided to repost it anyway with today's date? Or MU doesn't realize it is not a new update? Either way that doesn't say much about the MU internal process. I've seen many instances of updates on MU being reposted as 'new' but are really old updates, or updates that were released weeks or months before the posting date on MU, as if MU just got around to it or wasn't aware until much after the fact that an update was available. I know I'm not the only one who has noticed and commented on this. conversely, there are important updates that users should be notified about immediately that MU isn't even aware of. I think MU relies mainly on user posts to be alerted when new updates are available.And MU wonders why people don't pluck down money for the paid version of the MU software/service. The only rational explanation I can think of as to why MU reposts old updates as new, is the argument that it is a public service to make people aware of important updates, so it triggers or comes up on peoples watch list. But that is bogus, because for the people that already have the update, it's wasting their time to receive a notices about old updates, only to find they already have that update, and in most cases, like this one, received it AGES AGO (in software time).Now, it is true HP no longer provides drivers for out of the box anymore or directly online. If you purchase an HP in the last year or so, you are instructed to visit the HP website and are guided to download the terrible HP Easy Start software, which is nothing but a downloader stub. The problem with that is the Easy Start stub not only downloads the proper driver, but then proceeds to insist on installing tons of crap ware, 'customer feedback' software (aka telemetry spyware), and sign you up for the HP ink program, and so on. Good luck trying to locate the actual downloaded driver files only if you want to keep a copy for later offline install or backup. so, definitely, get a copy of the version 5.1 if you don't already have it, it will likely be the last from Apple. Fortunately, there hasn't been any radical change in the printer driver architecture under OSX / macOS, and at least for me, the drivers on this 5.1 update have worked on every release from Mavericks to Mojave. AVOID the HP Easy Start downloader if you can.

I sometimes find the Java setup on my various Apple devices to be a mystery.
Recently, I was trying to get a Java applet to run in the same way on 2 iMacs and my MacBook Air. The applet is a simple vpn client from Juniper that lets me access a Citrix Desktop from any Mac that I can install the Citrix receiver client on so I can work on 'Company stuff' from a large screen iMac when I'm sat at home or from my MacBook when I'm on the road (it works fine over 3/4G).
The first thing is that you have to do some configuring of both Java and Safari to get the applet to run at all.
Once that was all done, I could log in from all my Macs, fire up the applet and establish a secure connection.
On two of the Macs, as soon as I fired up the Citrix app, the Java vpn window would show 'error'. The console showed a Java crash. But on the third Mac, everything worked fine. I made sure that the Safari and Java preferences were set the same on each machine but still no joy. Then I remembered that I had done some Java development in the past and installed various jdks from Oracle so I ran:
in Terminal on each machine. I keep everything up to date via the Java control panel (currently 1.7xx soon to be 1.8) so was surprised to see this:
That was on the working Mac. Then I remembered the difference between 'System' Java, Java plugins, and Java development kits. Simply put, you can have multiple versions of Java in different places. What was happening on the not-working Macs was that the jdk versions were being used, and the Juniper vpn client won't work with them.
To fix things for the moment I simply removed the jdk folders.
And then checked that the reported version of Java was 1.6 on each Mac. Web applets still use the up to date, secure version 1.7 plugin.
[crarko adds: I believe Oracle has said that eventually Java will no longer support applets at all, on any platform.]