Disable fading detection on 1.21.6+ for now.

Might be worth revisiting once a proper fork of Immersive Portals appear for newer versions.

core/src/main/java/com/seibel/distanthorizons/core/wrapperInterfaces/modAccessor/ImmersivePortalsAbstractAccessor.java

@@ -196,6 +196,7 @@ public abstract class ImmersivePortalsAbstractAccessor implements IImmersivePort
 	 */
 	private boolean isPortalVisibleRightNow() {
 		Supplier<?> frustumSupplier = getFrustumSupplier();
+		if (frustumSupplier == null) return false;
 		for (Object portal : getGlobalPortals(getClientLevel())) {
 			if (!shouldSkipRenderingPortal(portal, frustumSupplier)) {
 				return true;