Hi. I'm working on the video game called Xonotic[1] that was based on
the Quake source code[2]. This code was originally released under the
terms of GNU GPLv2 and I can't find if it has the "or any later version"
clause. I want to license my code additions under GPLv3+ or AGPLv3+. Can
I do this?

[1]: https://xonotic.org/
[2]: https://github.com/id-Software/Quake