A dependency for gtkradiant seems completely unobtainable in Xubuntu 22.04

[Blaster9078]

I went to download it from the homepage, following the installation instructions there. During the step where you run "ldd" to find the dependencies, "libpangox" was completely undownloadable. The apt-get install command returned "Package is not available, but is refered to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source".
I tried adding different sources, installing the package through a .deb gotten from here(https://packages.ubuntu.com/bionic/libpangox-1.0-0) and nothing works. Am I doing something wrong due to my inexpertise with Linux, or is the package completely unavailable?

[TTimo]

Too many distros obsoleting too many libraries to even maintain source compatibility. Your best option might be the ongoing efforts to move radiant over to flatpak (#574)