Clean up broken duckquill submodule references

public/closable.js

@@ -0,0 +1,27 @@
+const closable = document.querySelectorAll("details.closable");
+
+closable.forEach((detail) => {
+	detail.addEventListener("toggle", () => {
+		if (detail.open) setTargetDetail(detail);
+	});
+});
+
+function setTargetDetail(targetDetail) {
+	closable.forEach((detail) => {
+		if (detail !== targetDetail) {
+			detail.open = false;
+		}
+	});
+}
+
+document.addEventListener("click", function (event) {
+	const isClickInsideDetail = [...closable].some((detail) =>
+		detail.contains(event.target)
+	);
+
+	if (!isClickInsideDetail) {
+		closable.forEach((detail) => {
+			detail.open = false;
+		});
+	}
+});