Previews how a GTK4/AGS widget actually looks by taking a fullscreen screenshot on an empty niri workspace and reading it back as visual feedback, to check that implemented styles, layout and colors came out as intended. Use when the user wants to preview, visually check or screenshot a widget's appearance — e.g. "見た目を確認", "視覚的に確認したい", "プレビュー", "スクショ撮って", "how does it look". For panels that appear only on user action (notification / player / launcher), it opens them via the request handler before capturing.
2026-06-04