mat-drawer-content problem setting css overflow

Question

I have the following code

<mat-drawer-container autosize style="display: inline;">
    <mat-drawer class="transparent h100 no-overflow"  #drawer mode="side">
        <app-classi-sezioni-anni-list>
        </app-classi-sezioni-anni-list>
    </mat-drawer>
    <mat-drawer-content class="no-overflow">
    </mat-drawer-content>
<mat-drawer-container>

class no-overflow is

.no-overflow {
    overflow:hidden !important;
}

I would expect the scrollbars to disappear...instead they're there. Inspect shows me this

The overflow auto is barred which should mean the no-overflow class should rule...but the scrollbars are there. If in inspect I uncheck the overflow auto, they disappear..... But as far as I know the fact they are barred means they have no effect...and anyway I cannot override that setting.