Unused dependencies not removed when uninstalling a snap program

[ardour]

I'm running Xubuntu 22.04 LTS.

Here's my steps in recreating this issue:

1. I run snap list in the Terminal, this is what my snap list output looks like:

    Name Version Rev Tracking Publisher Notes
    bare 1.0 5 latest/stable canonical✓ base
    core 16-2.58.3 14946 latest/stable canonical✓ core
    core20 20230404 1879 latest/stable canonical✓ base
    firefox 112.0.2-1 2605 latest/stable/… mozilla✓ -
    gnome-3-38-2004 0+git.6f39565 140 latest/stable/… canonical✓ -
    gtk-common-themes 0.1-81-g442e511 1535 latest/stable/… canonical✓ -
    snapd 2.59.1 18933 latest/stable canonical✓ snapd

2. I install and uninstall KompoZer:

I installed KompoZer with this command:

    sudo snap install kompozer

After I installed KompoZer, these dependencies alongside KompoZer were installed:

    core18
    gtk2-common-themes
    kompozer

After I uninstall KompoZer:

    sudo snap remove kompozer --purge

The dependencies for KompoZer were still listed in snap list:

    Name Version Rev Tracking Publisher Notes
    bare 1.0 5 latest/stable canonical✓ base
    core 16-2.58.3 14946 latest/stable canonical✓ core
    core18 20230320 2721 latest/stable canonical✓ base
    core20 20230404 1879 latest/stable canonical✓ base
    firefox 112.0.2-1 2605 latest/stable/… mozilla✓ -
    gnome-3-38-2004 0+git.6f39565 140 latest/stable/… canonical✓ -
    gtk-common-themes 0.1-81-g442e511 1535 latest/stable/… canonical✓ -
    gtk2-common-themes 0.1 13 latest/stable canonical✓ -
    snapd 2.59.1 18933 latest/stable canonical✓ snapd

Snap is leaving behind unused dependencies after uninstalling the snap that uses them.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.