diff --git a/assets/css/components/tom-select_extensions.css b/assets/css/components/tom-select_extensions.css
index abac05b5..b0529c25 100644
--- a/assets/css/components/tom-select_extensions.css
+++ b/assets/css/components/tom-select_extensions.css
@@ -39,3 +39,8 @@
     background: var(--bs-body-bg);
 }
 
+.ts-dropdown .optgroup-header {
+    color: var(--bs-tertiary-color);
+    background: var(--bs-body-bg);
+    cursor: default;
+}