Enable 256 color-mode only if VT sequences are available.

wincon/pdcsetsc.c

@@ -89,7 +89,16 @@ void PDC_set_title(const char *title)
 int PDC_set_blink(bool blinkon)
 {
     if (pdc_color_started)
-        COLORS = 256;
+    {
+        COLORS = 16;
+        if (PDC_can_change_color()) // is_nt
+        {
+            if (SetConsoleMode(pdc_con_out, 0x0004)) // VT
+                COLORS = 256;
+
+            SetConsoleMode(pdc_con_out, 0x0010); // LVB
+        }
+    }
 
     if (blinkon)
     {