diff --git a/arduino-ide-extension/src/browser/style/sketchbook.css b/arduino-ide-extension/src/browser/style/sketchbook.css
index def804acb..a0ab90ead 100644
--- a/arduino-ide-extension/src/browser/style/sketchbook.css
+++ b/arduino-ide-extension/src/browser/style/sketchbook.css
@@ -65,3 +65,8 @@
 .theia-TreeNode.theia-mod-selected .sketchbook-commands-icons {
   display: block;
 }
+
+.theia-Tree:focus .theia-TreeNode.theia-mod-selected,
+.theia-Tree .ReactVirtualized__List:focus .theia-TreeNode.theia-mod-selected {
+  background: var(--theia-list-inactiveSelectionBackground);
+}