diff --git a/kf5-kwindowsystem.spec b/kf5-kwindowsystem.spec
index c816d1b..63d89a0 100644
--- a/kf5-kwindowsystem.spec
+++ b/kf5-kwindowsystem.spec
@@ -40,6 +40,7 @@ BuildRequires:  qt5-qttools-devel
 BuildRequires:  qt5-qtx11extras-devel
 
 %if 0%{?tests}
+BuildRequires: openbox
 BuildRequires: weston
 BuildRequires: xorg-x11-server-Xvfb
 %endif