diff --git a/packages/core/src/browser/style/view-container.css b/packages/core/src/browser/style/view-container.css
index f284cc922869c..54f69957bf2ee 100644
--- a/packages/core/src/browser/style/view-container.css
+++ b/packages/core/src/browser/style/view-container.css
@@ -58,6 +58,7 @@
     line-height: var(--theia-view-container-title-height);
     z-index: 10;
     color: var(--theia-sideBarSectionHeader-foreground);
+    font-weight: 700;
 }
 
 .theia-view-container .part > .header .theia-ExpansionToggle {