spiffeeroo
You may want to play around with alsamixer. Some audio cards have really low volume on some of the mixers like PCM out of the box on Linux.
For a lot of people, louder audio subjectively means better sounding audio. (Loudness wars for audio mastering for example.)
Try installing kwallet-pam. It will remember your secrets through PAM when you log in. Arch does not have kwallet-pam installed by default unless you install via plasma-meta package.
If you use Chromium, you will not be asked for creating a password store as well so that is another bonus for kwallet-pam.
Arch and RHEL enable zswap by default. Regular x86_64 Ubuntu and Debian do not have zswap nor zram enabled by default.
A lot of dark chocolate on the market contain milk even though they are not supposed to since they are processed with the same equipment. Some brands list milk in their dark chocolate ingredient label. Perhaps OP is very sensitive to that certain sour flavour.
American chocolates (like Hershey's) tend to taste more sour because they have more sugar and less cacao. The milk also tends to have a more butyric acid taste for some reason. Perhaps the difference is how the milk is treated, but those are trade secrets.
The Ubuntu based distros may have this phased update thing. That AskUbuntu link has a command to override APT package manager to install the held-back packages.
Ubuntu tends to hold back system critical packages in case there are issues. Systems with certain install UUIDs will be 'guinea pigs' and install these packages before everyone else. You can override this behavior and disable phased updates on that particular computer.
WebP can be lossless or lossy compression. However, it is not easily apparent which compression mode is used for a given WebP file.
Google says lossy WebP is 25 percent smaller than JPEG and lossless WebP is 25 percent smaller than PNG.
Check if you have qt5-imageformats package installed. It is an optional dependency for kio-extras package that is not installed by default on Arch distros.
I am pretty sure webp works with the wallpaper picker on plasma5 from my experience.