All the following might have something to do with “minimal install” being ticked:
Getting Started > Updates and Extras > Additional Themes has a Remove button although nothing was installed;
Getting Started > Optional Tasks > Firewall has no effect because gufw
is not installed;
Getting Started > Optional Tasks > Backups has no effect because deja-dup
is not installed;
Getting Started > System Specifications > Detailed fails because inxi
is not installed;
Getting Started > System Specifications > Storage also shows nothing, but it is not clear what is causing that.
Edit: And (Gnome) Disks is described as “pre-installed”, but “minimal install” omits it.