I noticed our teachers have difficulties to manipulate the tertiary menu because it does not look like a menu.

I propose css tweak to make the tertiary menu more clear ($brandcolor has to be replaced with your choosen brandcolor in boost parameters):

.tertiary-navigation .tertiary-navigation-selector .dropdown-toggle{

font-size:1.2rem!important;

}

.tertiary-navigation .tertiary-navigation-selector .dropdown{

border:3px solid $brandcolor;

border-radius:0.5rem;

padding-left:3px;

padding-right:3px;

} 

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