Trying to use the latest version of Polysit on a 1.20.4 server with Via* mods installed causes 1.20.2 clients to be unable to join.

[ArkoSammy12]

Environment

• Minecraft: 1.20.4 Fabric server
• Polysit: polysit-0.5.3+mc.1.20.1.jar
• Polymer: polymer-bundled-0.7.5+1.20.4.jar
• Loader: Fabric Loader 0.15.6
• Java: Adoptium JDK 17

To reproduce

1. Create and start a Fabric server with Fabric API, Polymer, PolySit, ViaVersion, ViaFabric and ViaBackwards.
2. Launch a 1.20.2 client.
3. Try to join server with 1.20.2 client.

Expected results

Being able to join the 1.20.4 server with a 1.20.2 client

Actual results

The 1.20.2 client cannot join the 1.20.4 server

Anything else?

The client will be met with the following image

The logs in the client are be the following:

https://mclo.gs/3cifKtI

Strangely enough, this issue doesn't happen with 1.20.1 clients and below. This problem goes away when I remove Polysit from the server's mods, so I imagine that Polysit is having some get-along issues with the Via* mods. However the issue could go beyond just Polysit. This could also be an issue with Polymer itself xd.

[Ampflower]

Likely a Polymer or Fabric API bug; it's failing on 1.20.4's experimental mobs, which aren't present in 1.20.2 and older.

That or Via* doesn't know how to omit the experimental mobs for older clients.

[Ampflower]

Very likely Polymer's bug, reproduced with Fabric API + ViaFabric + Polymer + Polyfactory.

[ArkoSammy12]

I see. I guess the usage of PolySit triggers something in Polymer causing the issue to happen. I'm gonna close this issue now

[Ampflower]

So we don't duplicate work; am opening an issue there.

[ArkoSammy12]

So we don't duplicate work; am opening an issue there.

Thank you 👍🏻