diff --git a/css/userChrome-files/sidebar.css b/css/userChrome-files/sidebar.css
index 57c717f..fcf9176 100644
--- a/css/userChrome-files/sidebar.css
+++ b/css/userChrome-files/sidebar.css
@@ -50,10 +50,12 @@ hbox#sidebar-search-container textbox#search-box {
 .sidebar-placesTreechildren::-moz-tree-image {
   fill: var(--in-content-page-color)!important
 }
-#sidebar-header,
-.sidebar-splitter {
+#sidebar-header {
   border-color: hsla(240,5%,5%,.1)!important
 }
+.sidebar-splitter {
+  border-color: var(--tone-9)!important
+}
 .deck .instructions,
 .item-title {
   color: var(--in-content-page-color)!important
diff --git a/userChrome.css b/userChrome.css
index 2386a62..b7f8bba 100644
--- a/userChrome.css
+++ b/userChrome.css
@@ -1129,10 +1129,12 @@ hbox#sidebar-search-container textbox#search-box {
 .sidebar-placesTreechildren::-moz-tree-image {
   fill: var(--in-content-page-color)!important
 }
-#sidebar-header,
-.sidebar-splitter {
+#sidebar-header {
   border-color: hsla(240,5%,5%,.1)!important
 }
+.sidebar-splitter {
+  border-color: var(--tone-9)!important
+}
 .deck .instructions,
 .item-title {
   color: var(--in-content-page-color)!important