Banner
One full-bleed line about the whole session, not the page — impersonation, an unreachable backend, a job still running. Alert is the in-page box; this is the strip under the top bar. Dismissible only if you pass onDismiss.
Playground
Full-bleed, one line, about the session rather than the page. It has no title and no second line on purpose — anything that needs those is an Alert on the page it concerns.
<Banner
tone="brand"
icon={BrainIcon}
action={<BannerAction href="/brain/status">Check status</BannerAction>}
>
Working on hydrating your Second Brain.
</Banner>Working on hydrating your Second Brain. #455 in queue