I have blocked access to
Appearance – Themes
Appearance – Customize
Appearance – Widgets
edit- Dashboard is unchecked (disabled)
They can view it, that is great.
The problem is if they go to screen options, they can choose to see the Welcome section. Once this happens, they have access to Customize and a bunch of other options – like change your theme completely, widgets and so on.
It seems these options should not be allowed if they manually type in the link as well.