Alder's developer bar, as a design-system element: a collapsed bar and an expanded tabbed panel, server-rendered, with monospace code.
Open, every section shows (no tab switching); collapsed, only the bar. The server picks with open.
SELECT id, title FROM posts WHERE published = 1 ORDER BY id DESC;
With the script, the buttons switch sections and toggle open. This one starts collapsed: click a tab.
SELECT id, title FROM posts; UPDATE posts SET title = ? WHERE id = ?;
{"page": "home"}A server that patches the panel's inner content need not render hidden or aria-selected: the script re-applies the selection. "Patch" below replaces the panel's content with markup that has neither; the chosen section stays the only one showing.