During routine maintenance I noticed some packages "have been kept back":
The following packages have been kept back:
gnome-control-center-data isc-dhcp-client isc-dhcp-common
0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.
I have read "The following packages have been kept back:" Why and how do I solve it? but the reasons given there weren't satisfactory. apt-mark showhold produces empty output.
Previously I have seen this message (packages kept back) when upgrading curl which changed dependency from libcurl3 to libcurl4. But this time, taking gnome-control-center-data as an example, there's no change in dependency packages:
$ apt list gnome-control-center-data -a
Listing... Done
gnome-control-center-data/jammy-updates 1:41.7-0ubuntu0.22.04.4 all [upgradable from: 1:41.7-0ubuntu0.22.04.1]
gnome-control-center-data/now 1:41.7-0ubuntu0.22.04.1 all [installed,upgradable to: 1:41.7-0ubuntu0.22.04.4]
gnome-control-center-data/jammy-security 1:41.4-1ubuntu13.2 all
gnome-control-center-data/jammy 1:41.4-1ubuntu12 all
$ apt show gnome-control-center-data=1:41.7-0ubuntu0.22.04.1
...
Depends: dconf-gsettings-backend | gsettings-backend
Breaks: gnome-control-center (<< 1:3.7.92-2~)
Replaces: gnome-control-center (<< 1:3.7.92-2~)
...
$ apt show gnome-control-center-data=1:41.7-0ubuntu0.22.04.4
...
Depends: dconf-gsettings-backend | gsettings-backend
Breaks: gnome-control-center (<< 1:3.7.92-2~)
Replaces: gnome-control-center (<< 1:3.7.92-2~)
...
I know I can force an upgrade by specifying the packages on the command line (so I'm not in need of a quick solution). But this has occurred multiple times recently, each time involving distinct packages. I would like to know the reason (cause) behind this.