The Topbar presents the current application, time, device facts and short-lived notification text. On a narrow display these compete for the same row. Allocation and bounded replacement determine what remains legible when the room runs out.
Notification text can temporarily take the application-title position, then yield it back. Date, time and configured widgets remain part of the layout instead of wrapping into accidental extra rows.
The component has its own repository and package. It speaks to the resident shell over the existing interface. Its separate-process path and exact pinned integration are explicit; drawing a status does not make the bar the owner of that status.
What remains open
- Narrow-screen layout, notification timing and touch acceptance remain physical checks.
- The future pull-down surface has unresolved product decisions.