The release notes collection issue from GNOME 48 components is now open on GitLab: Collect items for GNOME 48 (#52) · Issues · Teams / Websites / release.gnome.org · GitLab
Whenever you land a new feature, fix a noteworthy issue, or in general want to include something relevant for the release notes, feel free leave a comment there. This includes core applications, components, and SDK modules.