Strokes carry an object (0 for older projects, nothing written for 0). The
tracker follows every object in one pass and the mattes are united; the
confidence of a frame is the least sure object's. Object picker in the Layer
panel's bar; roto.options/stroke/clearStrokes/status take or report objects.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>