diff --git a/src/platform/web/ui/css/avatar.css b/src/platform/web/ui/css/avatar.css
index 6e68236f..b2405896 100644
--- a/src/platform/web/ui/css/avatar.css
+++ b/src/platform/web/ui/css/avatar.css
@@ -37,6 +37,7 @@ limitations under the License.
 }
 
 /* work around postcss-css-variables limitations and repeat variable usage */
+
 .hydrogen .avatar.size-128 {
     --avatar-size: 128px;
     width: var(--avatar-size);
@@ -53,6 +54,14 @@ limitations under the License.
     font-size: calc(var(--avatar-size) * 0.6);
 }
 
+.hydrogen .avatar.size-52 {
+    --avatar-size: 52px;
+    width: var(--avatar-size);
+    height: var(--avatar-size);
+    line-height: var(--avatar-size);
+    font-size: calc(var(--avatar-size) * 0.6);
+}
+
 .hydrogen .avatar.size-30 {
     --avatar-size: 30px;
     width: var(--avatar-size);