private void onContextUpdate(ContextUpdateEvent e) {
        e.getSubject(ServerPlayer.class).ifPresent(p -> requestUpdate(p.getUUID()));
    }
Calls {@link net.minecraft.server.players.PlayerList#sendPlayerPermissionLevel(ServerPlayer)} when a players permissions change.
neoforge/src/main/java/me/lucko/luckperms/neoforge/listeners/NeoForgeCommandListUpdater.java