Use <details> und <summary> instead of panel-collapse

src/pretix/static/pretixbase/js/details.js

@@ -0,0 +1,55 @@
+/*global $ */
+
+$(function () {
+    "use strict";
+
+    var isOpera = Object.prototype.toString.call(window.opera) == '[object Opera]';
+
+    $("details summary, details summary a").click(function (e) {
+        var $details = $(this).closest("details");
+        var isOpen = $details.prop("open");
+        var $detailsNotSummary = $details.children(':not(summary)');
+        if ($detailsNotSummary.is(':animated')) {
+            e.preventDefault();
+            return false;
+        }
+        if (isOpen) {
+            $details.removeClass("details-open");
+            $detailsNotSummary.stop().show().slideUp(500, function () {
+                $details.prop("open", false);
+            });
+        } else {
+            $detailsNotSummary.stop().hide();
+            $details.prop("open", true);
+            $details.addClass("details-open");
+            $detailsNotSummary.slideDown();
+        }
+        e.preventDefault();
+        return false;
+    }).keyup(function (event) {
+        if (32 == event.keyCode || (13 == event.keyCode && !isOpera)) {
+            // Space or Enter is pressed — trigger the `click` event on the `summary` element
+            // Opera already seems to trigger the `click` event when Enter is pressed
+            event.preventDefault();
+            $(this).click();
+        }
+    });
+
+    $('details').each(function () {
+        var $details = $(this),
+            $detailsSummary = $('summary', $details).first(),
+            $detailsNotSummary = $details.children(':not(summary)');
+        $details.prop('open', typeof $details.attr('open') == 'string');
+        if (!$details.prop('open')) {
+            $detailsNotSummary.hide();
+        } else {
+            $details.addClass("details-open");
+        }
+        $detailsSummary.attr({
+            'role': 'button',
+            'aria-controls': $details.attr('id')
+        }).prop('tabIndex', 0).bind('selectstart dragstart mousedown', function () {
+            return false;
+        });
+    });
+});