add purge cache

index.html

@@ -9,6 +9,7 @@
 		<link rel="icon" href="light-favicon.png" media="(prefers-color-scheme: dark)" />
 		<link rel="stylesheet" href="https://cdn.hello.coop/css/hello-button.css" />
 		<script src="https://cdn.hello.coop/js/hello-dev-wc-footer.js" defer></script>
+		<script src="/purge-cache.js" defer></script>
 		<style type="text/css">
 			html,
 			body {

public/purge-cache.js

@@ -0,0 +1,12 @@
+/**
+ * If the browser back button is clicked, flush the cache.
+ * This ensures the user always sees an accurate and up-to-date view based on their state.
+ * Reference: https://stackoverflow.com/questions/8788802/prevent-safari-loading-from-cache-when-back-button-is-clicked
+ */
+(function () {
+	window.onpageshow = function (event) {
+		if (event.persisted) {
+			window.location.reload();
+		}
+	};
+})();