0. ALWAYS PROVIDE INFORMATION ABOUT MODLOADER (Fabric / Forge) AND MOD VERSION (For Example 1.19.2-8.2.10)

Java 1.20.2, Fabric 0.14.24, Multiplayer Server.

1. Describe the bug

When a player joins the server, if they had a backpack on when they had logged out, the backpack will not show and there is nothing in inventory or anything. However, if they jump out of the server and jump back in...the backpack is back on their back and everything is correct. The server and the client have no errors, so I am unsure where to look to determine where/what to look for. I have tried on multiple accounts/players too. Happens to Operators too.

2. Write steps to reproduce the bug

Have a backpack on, log off the server, and close out the Fabric loader. Start everything back up and log in to the server as normal.

3. What is expected behaviour

Backpack should stay.

@eliminster Did you find any solution?

does it happen everytime? Also what is your Cardinal components version?

A few, but they are mostly performance related for the server and clients. On the Server: BetterF3, BetterStats, Blur, Clumps, Chunks Fade-In, Sodium, Simple Voicechat, and their associated libraries. We have mostly a vanilla based player gameplay system. There are a few things we use for "enhancement" to vanilla. As mods outside of vanilla play, we have JEI, Travellers, Waystones, Graves, Tom's Simple Storage, Xaero's Minimap & Worldmap. Tom's was added a few days ago but the Backpack issue was going on beforehand. On the client's side: aside from the already established mods the unique mods are: 3D Skins, Indium, ModMenu, MouseTweaks, Shulkerbox Tooltips, Traveler's Backpack, Tom's, Simple Voicechat, Waystones, Xaero's Maps, and all of their associated libraries. All are up-to-date as of the last week. Where would you like me to help look?

I just wish to reiterate, that once we log in, we immediately jump out and go right back in, and the backpack is there. Plus, if we jump in and the pack is not there, the game still believes there is one equipped as you can not equip another backpack...if you try, it tells you that you are already wearing one. Not sure if that helps or hinders.

It happens every.single.time.

Our Cardinal version is 5.3.0 which I believe is the updated version.

is it possible for you to check if issue occurs with clean server only tb + required mods for tb to run?

Tiv,
Just spun up a brand new server with only the requirements of Travellers. Same thing.

More info for you though:

MC version - Java 1.20.2
Fabric Modloader - 0.14.24
Cloth - 12.0.109
Fabric API - 0.90.4
Travellers - 9.2.2
Cardinal - 5.3.0

I see there are a couple of updates I can do on those versions, but wanted to do this in baby steps in case you needed to collect more information from my test server.

-Keven

Also occurs very intermittently in server for Minecraft 1.20.1, Traveler's Backpack 9.1.8, Quilt Loader 0.21.2. It's happened to two of my players over the last couple of days. No pattern detected so far, other than as described above -- Player logged out with backpack on, logs back in and backpack is gone. One player had it reappear seemingly at random, I don't think they disconnected and reconnected.

do you use any other mods?

Okay, I'll check that with same version of everything like you, but in about 2 days when I'll have some free time.
Also more questions:
You do not play on LAN right?
Does it happen with every backpack? can you create brand new backpack and check if issue still occurs?
Do you have a lot of items in backpack?
Do you have client & server config synced?

We play on LAN computers but connect via an online host, but I assume you mean localhost, then no, we do not. As for trying out different packs, I am way ahead of you on that question. We have tried every backpack and, unfortunately, it produced the same results. It does not matter if it is chocked full of items or empty, same issue.

Same issue here. After launching the client, the first join on multiplayer does not have the backpack loaded. We have to disconnect and reconnect. It's not a problem if Trinkets integration is enabled.

Before moving my world to a dedicated server, i used to share the LAN connection with e4mc. Same issue there, for the people joining, but for me, as i was basically in single player, it worked fine.

Version 1.20.2-9.2.3 both client and server.

So you play on dedicated server now?

Yes. Self hosted.

When you asked, "Do you have client & server config synced?" can you elaborate on what you mean by that? Is there something else I am missing or should be doing on the server?

Ours is hosted with APEX.

When you asked, "Do you have client & server config synced?" can you elaborate on what you mean by that? Is there something else I am missing or should be doing on the server?

Basically it means that your configs on hosting (server) should have the same values like on the client (your pc). I mean only common config

Ahhh, then yes...they are synced.

I've just tested the server with same exact versions like yours and issue is not occuring... I can disconnect from server and connect again and backpack is still there

Well, if it did not happen the first go around for you, what would be the difference between my brand-new server and only the backpack mod installed and your server? Where can I look to help isolate it?

I've just tested the server with same exact versions like yours and issue is not occurring... I can disconnect from server and connect again and backpack is still there

Did you also close the client after disconnecting? Disconnecting and connecting again without leaving the client is the workaround we do, to get the backpack loaded.

Okay, I am able to reproduce the issue after closing the client

Okay, so I am able to reproduce issue on 1.20.2, but 1.20.1 seems to work correctly

I have one more question, do other people see that you wear a backpack? or they also do not see the backpack on your back until you relog?

Is it possible for you to test on your server the file I'll provide you via Discord? I think I've fixed the issue, but I'd need additional confirmation from someone who encountered the issue often

Okay so join my discord https://discord.gg/DxEbvrHu and ping me and we'll go further from that point

Where is your discord server link?

In previous message

Okay so join my discord https://discord.gg/DxEbvrHu and ping me and we'll go further from that point

I have one more question, do other people see that you wear a backpack? or they also do not see the backpack on your back until you relog?

No, backpacks are not rendered either. It's like they are not loaded at all. We haven't tried to place the backpack though.

I can also try the server, if needed sometime, mid next week. I'll reach out to you on Discord.

https://legacy.curseforge.com/minecraft/mc-mods/travelers-backpack-fabric/files?page=1&pageSize=20
https://modrinth.com/mod/travelersbackpack/versions
should be fixed