Greetings, I decided to investigate Guix's commit history and found out that the issue was introduced around the emacs-team merge. The change that I found would be most impactful to IGC is <fccc4fe53e>[1], which enabled tests for most Emacs packages.
From this, I deduced that the test was probably already failing anyway, but went unnoticed because tests weren't being run. I thus disabled the test as a "solution". I'm a bit worried that this might signal runtime issues, but since I couldn't find any major changes that could affect IGC, it seems this isn't, and might not be the case in the future. Thank you, Liliana for replying, and any others for your attention. [1] <https://codeberg.org/guix/guix/commit/fccc4fe53e1a05ae6a728e5d92a3a82b46a49096> Regards, -- Gabriel Santos