diff --git a/src/Fl_Screen_Driver.cxx b/src/Fl_Screen_Driver.cxx
index 4e721d28e..ec1474cc5 100644
--- a/src/Fl_Screen_Driver.cxx
+++ b/src/Fl_Screen_Driver.cxx
@@ -493,6 +493,9 @@ float Fl_Screen_Driver::default_scale_factor()
   else {
     factor = desktop_scale_factor();
   }
+  // checks to prevent potential crash (factor <= 0) or very large factors
+  if (factor < 0.25) factor = 0.25;
+  else if (factor > 10.0) factor = 10.0;
   return factor;
 }
 
diff --git a/src/drivers/X11/Fl_X11_Screen_Driver.cxx b/src/drivers/X11/Fl_X11_Screen_Driver.cxx
index b6d333365..1e1f8a265 100644
--- a/src/drivers/X11/Fl_X11_Screen_Driver.cxx
+++ b/src/drivers/X11/Fl_X11_Screen_Driver.cxx
@@ -1346,7 +1346,7 @@ static bool gnome_scale_factor(float& factor) {
         strcpy(str, str2);  v = v2;
       }
       ubuntu_f = v/8.;
-      printf("com.ubuntu.user-interface  scale-factor name=%s value=%d factor=%g\n", str, v, ubuntu_f);
+      // printf("com.ubuntu.user-interface  scale-factor name=%s value=%d factor=%g\n", str, v, ubuntu_f);
       g_variant_iter_free_f(iter);
       g_variant_unref_f(gvar);
       g_object_unref_f(gset);
@@ -1363,7 +1363,7 @@ static bool gnome_scale_factor(float& factor) {
       unsigned v;
       g_variant_get_f(gvar, "u", &v);
       ubuntu_desktop_f = v;
-      printf("org.gnome.desktop.interface  scaling-factor value=%u factor=%g\n", v, ubuntu_desktop_f);
+      // printf("org.gnome.desktop.interface  scaling-factor value=%u factor=%g\n", v, ubuntu_desktop_f);
       g_variant_unref_f(gvar);
       g_object_unref_f(gset);
       if (ubuntu_desktop_f != 1) {
@@ -1388,7 +1388,7 @@ static bool gnome_scale_factor(float& factor) {
       //str = (char*)g_variant_get_type_f(gvar); // -> "i"
       g_variant_get_f(gvar, "i", &v);
       gnome_f = v;
-      printf("org.gnome.settings-daemon.plugins.xsettings  overrides name=%s value=%d factor=%g\n", str, v, gnome_f);
+      // printf("org.gnome.settings-daemon.plugins.xsettings  overrides name=%s value=%d factor=%g\n", str, v, gnome_f);
       free(str);
       break;
     }