Use <details> and <summary> for variations

src/pretix/static/pretixpresale/scss/_event.scss

@@ -65,6 +65,20 @@
         line-height: inherit;
     }
 }
+details.item-with-variations {
+    list-style: none;
+}
+details.item-with-variations > summary::-webkit-details-marker {
+  display: none;
+}
+
+details summary {
+    -moz-user-select: none;
+    -ms-user-select: none;
+    -webkit-user-select: none;
+    user-select: none;
+}
+
 .radio .variation-description {
     padding-left: 20px;
 }