Comment 4 for bug 1878010

The gtk+3.0 autopkgtests regressions are caused by the downgrading of librsvg2-common from a depends to a recommends. I have reverted this in https://salsa.debian.org/gnome-team/adwaita-icon-theme/-/commit/f203171792b9c45b573483ad25046f0a4dd81601, and this is ready for sponsoring to focal again.