Revisit notification placement for maintenance

Balance the placement of maintenance notifications with visibility and user experience, intersection with existing UI elements people interact with, and a desire to have them see it and read it. It can be dismissed.

The issue names no files, tests, or entry points. Start by locating the maintenance notification UI and reviewing where it overlaps with existing interactive elements. Before implementation, establish the intended placement, visibility, dismissal behavior, and user-experience criteria so completion can be evaluated.

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