Regarding packages held back during upgrade to bullseye, see this thread and Issue 2103. You generally don’t need Cockpit to manage updates. The Cockpit message is a red herring. I had several packages held back, but after a couple of days of automatic updates, I was left with just one package that I ultimately had to handle manually. As mentioned in the thread, you can use “apt -s install packageX” to see what will happen if you manually update a package. I looked at the package dependencies and found that I had to remove libgc1c2 to get libgc1 installed:
god@freedombox:~$ sudo apt-get remove libgc1c2
[sudo] password for god:
Reading package lists… Done
Building dependency tree… Done
Reading state information… Done
The following package was automatically installed and is no longer required:
libreadline7
Use ‘sudo apt autoremove’ to remove it.
The following additional packages will be installed:
guile-2.2-libs libgc1
The following packages will be REMOVED:
libgc1c2
The following NEW packages will be installed:
libgc1
The following packages will be upgraded:
guile-2.2-libs
1 upgraded, 1 newly installed, 1 to remove and 0 not upgraded.
Need to get 5160 kB of archives.
After this operation, 39.9 kB of additional disk space will be used.