calendar (but maybe also other tools) - install rights - individuel rights
In the C2 the situation was like this:
Install rights for a tool (here calendar) - individual rights gave a table with green and red bullets per course users, both under the tabs Users and Course Groups. You could change the rights by clicking on the bullet (changed colour)
In C3 this is only the case under the tab Course Groups. Under the tab Users, you only get a table that is not reflecting the installed rights (I setted reading rights for every user, edit/delete only for me), there are no bullets at all and you can not change them.