Maybe i don’t understand how AUR works as i recently decided to move from Microsoft Windows to Manjaro Linux which is ArchLinux based but looking at the SWI-Prolog announcement revision i saw that AUR was not updated yet from 8.3.29-2 to 8.4.0 though i suppose this package is also concerned ?
https://aur.archlinux.org/packages/swi-prolog-devel
PS: I know some prefer Ubuntu but ArchLinux is much more reactive on the Linux part as it works like SWI-Prolog with rolling updates, knowing to be fair that i use Manjaro Linux to have a supplementary testing level before releases … which makes a more than serious competitor to Microsoft Windows in the Manjaro KDE Plasma version (easy installation, stable updates, nice looking, great community support, with all the power of Linux).