I noticed that there are two entries for "system Monitor", "Characters" and "Logs" when I search in Dash with different icons, but launching apparently the same app.
After reading this post I checked the /var/lib/snapd/desktop/applications folder and surely enough I found that there are the three Gnome apps which I never manually installed.
Is there a reason why Ubuntu comes with these snaps pre-installed while having the normal apps installed as well? And is it safe to uninstall them?
Ubuntu by default does not come with both a snap and a regular version installed by default. You must have manually installed the regular versions at some point, unless perhaps an OS upgrade to a newer version over an older version did install the snaps but did not remove the regular versions.
Yes, it is fully safe to uninstall them and use the versions from the repositories instead. I do this myself and did not encounter any negative effect. As a matter of fact, snaps are not (yet?) integrated with the APT management system, so removing snaps will not in any way affect your regularly installed packages, nor remove for example the ubuntu-desktop metapackage.
