Method _drawerHasBackdrop

src/material/sidenav/drawer.ts:1074–1080

(drawer: MatDrawer | null)

  // Whether argument drawer should have a backdrop when it opens
  private _drawerHasBackdrop(drawer: MatDrawer | null) {
    if (this._backdropOverride == null) {
      return !!drawer && drawer.mode !== 'side';
    }

    return this._backdropOverride;
  }
}