- A brush region no longer disappears after switching color and back: added objects are kept in the frame data, and
strokes not applied yet are applied to their color before the color or frame changes or a run starts.
- Objects added on a frame (brush, points, text) are shared by every color; each color selects its own. Removing one
removes it for all colors.
- Shift while painting does the opposite of the tool: the brush erases from the mark, the eraser paints back.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>