When you have more than 4 items, we recommend that you add a “see more” button. We only provide the layout in Fluid vanilla library. It is automatically added with the React and Angular Fluid component (cf. storybook links above).
Since breadcrumbs provide a navigation, it’s a good idea to add a meaningful label such as aria-label="breadcrumb" to describe the type of navigation provided in the <nav> element, as well as applying an aria-current="page" to the last item of the set to indicate that it represents the current page.