diff --git a/gtk/theme/HighContrast/_common.scss b/gtk/theme/HighContrast/_common.scss
index b543a5bf3c..f4f01adc78 100644
--- a/gtk/theme/HighContrast/_common.scss
+++ b/gtk/theme/HighContrast/_common.scss
@@ -1380,7 +1380,7 @@ GtkTreeView.view.progressbar { //Progressbar in treeview cells
   &.trough { @extend .scrollbars-junction; }
   &.slider {
     border-radius: 20px;
-    border: 5px solid transparentize(mix($bg_color, $fg_color, 50%),0.99); //margin :/
+    border: 5px solid transparent; //margin
     background-color: mix($bg_color, $fg_color, 50%);
     &:backdrop, &:insensitive {
       background-color: mix($bg_color, $fg_color, 90%);
diff --git a/gtk/theme/HighContrast/gtk.css b/gtk/theme/HighContrast/gtk.css
index e0d588d2ec..3e6e475cd2 100644
--- a/gtk/theme/HighContrast/gtk.css
+++ b/gtk/theme/HighContrast/gtk.css
@@ -1594,7 +1594,7 @@ GtkTreeView.view.progressbar {
     border: none; }
   .scrollbar.slider {
     border-radius: 20px;
-    border: 5px solid rgba(127, 127, 127, 0.01);
+    border: 5px solid transparent;
     background-color: #7f7f7f; }
     .scrollbar.slider:backdrop, .scrollbar.slider:insensitive {
       background-color: #e5e5e5; }