Fixed
Breadcrumbs' bundled CSS used bare, one-word Tailwind utility classes (.static, .flex, .grow, etc.) applied globally across the entire Obsidian DOM, not just Breadcrumbs' own views. This collided with Excalidraw, whose own canvas element carries a literal class static for an unrelated purpose — at equal CSS specificity, Breadcrumbs' stylesheet won the cascade and forced the canvas to position: static, leaving Excalidraw drawings blank/invisible with Breadcrumbs enabled.
Every Breadcrumbs utility class is now namespaced with a bc: prefix (bc:static, bc:flex, ...), so Breadcrumbs' CSS can no longer collide with another plugin's own class names. Refs #761