--- a/widget/gtk/nsWindow.cpp
+++ b/widget/gtk/nsWindow.cpp
@@ -6927,17 +6927,17 @@ nsWindow::GetCSDSupportLevel() {
     if (sCSDSupportLevel != CSD_SUPPORT_UNKNOWN) {
         return sCSDSupportLevel;
     }
     const char* currentDesktop = getenv("XDG_CURRENT_DESKTOP");
     if (currentDesktop) {
         if (strcmp(currentDesktop, "GNOME") == 0) {
             sCSDSupportLevel = CSD_SUPPORT_FULL;
         } else if (strcmp(currentDesktop, "XFCE") == 0) {
-            sCSDSupportLevel = CSD_SUPPORT_FULL;
+            sCSDSupportLevel = CSD_SUPPORT_FLAT;
         } else if (strcmp(currentDesktop, "X-Cinnamon") == 0) {
             sCSDSupportLevel = CSD_SUPPORT_FULL;
         } else if (strcmp(currentDesktop, "KDE") == 0) {
             sCSDSupportLevel = CSD_SUPPORT_FLAT;
         } else if (strcmp(currentDesktop, "LXDE") == 0) {
             sCSDSupportLevel = CSD_SUPPORT_FLAT;
         } else if (strcmp(currentDesktop, "openbox") == 0) {
             sCSDSupportLevel = CSD_SUPPORT_FLAT;