SPIGOT-5841: New map colours broken

src/main/java/org/bukkit/craftbukkit/map/CraftMapView.java

@@ -164,7 +164,7 @@ public final class CraftMapView implements MapView {
             for (int i = 0; i < buf.length; ++i) {
                 byte color = buf[i];
                 // There are 208 valid color id's, 0 -> 127 and -128 -> -49
-                if (color >= 0 || color <= -49) render.buffer[i] = color;
+                if (color >= 0 || color <= -21) render.buffer[i] = color;
             }
 
             for (int i = 0; i < canvas.getCursors().size(); ++i) {