diff --git a/src/x11_init.c b/src/x11_init.c
index acfa793388..bd038090b1 100644
--- a/src/x11_init.c
+++ b/src/x11_init.c
@@ -1204,6 +1204,7 @@ GLFWbool _glfwConnectX11(int platformID, _GLFWplatform* platform)
         _glfwWaitEventsX11,
         _glfwWaitEventsTimeoutX11,
         _glfwPostEmptyEventX11,
+        _glfwPlatformSetWindowTitlebar,
         _glfwGetEGLPlatformX11,
         _glfwGetEGLNativeDisplayX11,
         _glfwGetEGLNativeWindowX11,