Block-level paragraphs in the WYSIWYG rendered/split view append PARAGRAPH_TRAILING_SPACE_Y (16px) after render_paragraph / render_paragraph_with_structural_keys so consecutive paragraphs are visibly separated. The same constant is applied after non-mermaid and mermaid code blocks for consistent separation from following content.
BLOCK_ITEM_SPACING_Y stays at 1px for egui item_spacing and viewport overscan math in show_viewport(). Per-block heights from the measurement pass (y_after - y_before) include the trailing space automatically, so scrollbar range and culling stay aligned.
List item body text does not use render_node for paragraphs; spacing between items is unchanged.