diff --git a/cmake/Dependencies.cmake b/cmake/Dependencies.cmake
index 220fdecb24..7f9587c228 100644
--- a/cmake/Dependencies.cmake
+++ b/cmake/Dependencies.cmake
@@ -96,7 +96,7 @@ search_dependency(VPX                 PACKAGE vpx)
 search_dependency(OPENAL              PACKAGE openal FRAMEWORK OpenAL)
 
 # XScreenSaver support.
-search_dependency(XSS                 LIBRARY Xss)
+search_dependency(XSS                 LIBRARY Xss OPTIONAL)
 # Qt5 Platform support library needs to be statically linked on Windows/Mingw.
 search_dependency(QT5PLATFORMSUPPORT  LIBRARY Qt5PlatformSupport)