Takinalis: /url works in Titan Icon because it messes with the client memory to put dev-only commands in player reach (you need to use /accesslevel 9 first). It won't work in Paragon Chat, because it doesn't modify the client in any way.
To be precise, if I understand the architectures involved, and to expand on the explanation, neither Icon nor Paragon Chat alter any of the game client files. That means they can coexist with one copy of the client, since in both cases Icon and Paragon Chat just need the client files, but don't touch them.
However, Icon tampers with
the running state of the client, which allows Icon to trick the game client into running even though there are no servers. It also tricks the client into allowing things that would ordinarily require enhanced permissions normal game players didn't have, but developers had either with special characters on the live servers or when running the game client in developer mode to test game development.
Paragon Chat, on the other hand, doesn't tamper with the running state of the game client, so the client actually thinks its running normally. Paragon Chat itself
emulates enough of the client-server protocol to trick the game client into thinking it has actually connected to a real server. The problem is that Paragon Chat itself doesn't yet understand everything a game client can do, so it cannot send the right messages to make certain things happen, like tell the game client that your character is currently flying (and thus to set the FLY bit and enable that movement mode). It also cannot tell the game client to allow things that Icon could enable by messing with the memory state of the game client.
Because Paragon Chat is in effect implementing the same features by a completely different means - figuring out the right network traffic to send in the right order and in the right way and with the right state persistence - that Icon did by just flipping a couple of bits in the game client's memory, *everything* that Icon did besides a few things related to how players entered input and saw motion has to be recreated from scratch. Which means if Icon did it, Paragon Chat
probably could do it in theory, but its also true that just because Icon does it, doesn't mean Paragon Chat
will do it, or even that Codewalker is currently capable of enabling it. For many features there might be a ton of work between here and there.
Why the difference? Because when its just you, you can play tricks with the game client to make it do anything. But when its part of a multi-user system like Paragon Chat, anything you do by hacking the local client might not be seen by everyone else, which defeats the purpose. Everything that happens must happen with actual network traffic and client-server messages, so they can be sent to everyone else in the right way so everyone sees (roughly) the same thing. And that's why Paragon Chat has to start from scratch.