This fork away from Ubuntu and use of apt-get in favor of the buggy Discover package and its installation method is really killing me and many others. In particular the Java virtual machine installed by default makes Libre Office run like a 3 legged chihuahua in deep snow when documents start exceeding hundreds of pages and contain multiple images. On my 7th gen i7 with 24Gig of RAM the JVM seems to limit itself to only 4Gig no matter what. The "standard" solution for this problem is to install Oracle Java. For Ubuntu based distros which haven't strayed needlessly from the PPA system this is simple.

Go here. http://ubuntuhandbook.org/index.php/2018/11/how-to-install-oracle-java-11-in-ubuntu-18-04-18-10/

Add PPA

Install Oracle Java.

Make it the default and Libre Office runs much better. It can consume the RAM it needs and has a snappy feel even when editing a document with thousands of pages and hundreds of images.

Sadly, that "fix" isn't available to KDE Neon users.
=====
E.g.:
sudo mkdir -p /var/cache/oracle-jdk11-installer-local
sudo cp jdk-11.0.3_linux-x64_bin.tar.gz /var/cache/oracle-jdk11-installer-local/
sha256sum mismatch jdk-11.0.3_linux-x64_bin.tar.gz
Oracle JDK 11 is NOT installed.
dpkg: error processing package oracle-java11-installer-local (--configure):
installed oracle-java11-installer-local package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
oracle-java11-installer-local
E: Sub-process /usr/bin/dpkg returned an error code (1)

=====

How is one supposed to install Oracle Java on KDE Neon now that KDE Neon has strayed too far from the PPA system?

I found the answer.

You have to install 12 from here: https://www.linuxuprising.com/2019/03/how-to-install-oracle-java-12-jdk-12-in.html

Alternatively do you really need Oracle's version of java or will OpenJdk (which should be readily available in the default repos) suffice?

Hi rolandh,
I also agree with airdrik, because I have openjdk-11-jre installed on my old desktop and I could say that LO Writer performs well in my old desktop with a document of two hundred (200) pages with a Pentium dual 3200E processor and 4Gb of RAM.
You could see an image here: https://imgur.com/i9o384M

Regards,

I personally do not like Oracle Java cause it appears that it doesn't come with some necessary community patches for fonts, with it being closed-source and all. Basically, some of my apps will end up with fugly aliasing for fonts when using Oracle Java, but work well with OpenJDK. Performance-wise I don't see much differences either. I don't really edit documents a lot, so I can't comment on LibreOffice's performance with OpenJDK, but I can comment on Minecraft, and that it's running just fine with it. From what I could recall (since it has been a few months since I last played Minecraft), the performance between Oracle Java and OpenJDK was rather comparable. Even if it was slightly lower, I'd still commit to it cause fugly fonts on the Java apps bothered me more.

nothing wrong with flash as long as you pay attention to what you're doing.