Fill bare gaps.

Finds unpainted triangles sitting next to a painted region and fills each with its dominant painted-neighbour colour. It grows inward one ring per Fill step (default 3), so it can close slivers a few triangles deep. It only ever touches bare faces — it never recolours a triangle you already painted.

• After painting two adjacent regions different colours, when zooming in shows bare unpainted slivers between them.
• Before export, as a general 'close the bare seams' pass.
• After Magic Fill stopped one triangle short of a clean boundary, leaving a thin unpainted gap.

1. Check tab → Fill bare gaps (Fill steps = 3 by default).
2. Click the button. Your colours grow into the bare slivers.
3. Zoom in to verify the seam is filled.
4. Ctrl+Z to undo if a gap should have stayed open.

• More steps fill wider gaps. 3 covers most slivers; raise it for bigger bare patches. Because it only fills unpainted faces, a high step count can't eat into your painted work.
• Running it before painting does nothing — it needs painted faces next to the bare ones.
• For stray painted flecks (a wrong-colour triangle inside a painted region), use Find speckles instead — this only fills bare faces.
• Right-click → Fill borders (whole mesh) runs the same action without switching tabs. The menu still uses the old "Fill borders" label.