Following up a tip of an ArcoLinux user we take a look at Pocillo-gtk-theme.
This theme seems to be developed by the UbuntuBudgie team is, who build it on the pop-os theme
who build it on the materia theme
So here you have 3 different themes to take a look at.
We will stay with pocillo.
We see that you can install it via AUR
trizen -S pocillo-gtk-theme-git
BUT you can also build the pocillo theme yourself.
This will come in handy IF the pkgbuild from AUR breaks for example.
We are just doing it to make an educational tutorial about building.
You see that on the github they used sudo apt install.
That means it will work on a debian/ubuntu based system BUT not on an ArchLinux.
With some common sense and a lot of patience you can make the translation between Ubuntu and ArchLinux.
That is exactly what we will do together in the video and install this theme as an end-result.
Here you can learn how to make a script
with the knowledge we acquired and
make sure we can install it quickly after next clean install.