diff --git a/static/themes/default/css/main.css b/static/themes/default/css/main.css
index 603b120bc..d6d7ec504 100644
--- a/static/themes/default/css/main.css
+++ b/static/themes/default/css/main.css
@@ -945,12 +945,20 @@ section.app-description {
 .notification {
     padding: 0.625rem 0.9375rem;
     border-left: 0.3125rem solid;
+    max-height: 100rem;  /* HACK: Very high value for closing transition. */
 }
 
 .notification:not(:first-child) {
     border-top: 1px solid var(--bs-border-color-translucent);
 }
 
+.notification.htmx-swapping {
+    opacity: 0;
+    overflow: hidden;
+    max-height: 0;
+    transition: opacity 0.3s, max-height 0.3s;
+}
+
 .notification-time {
     float: right;
     font-size: 0.8rem;