I don't know if what's going on is a bug or what, but something is wrong, and I hope you can help.

I log into a server, and it's okay for a couple seconds, but then I'm getting crashes as soon as the world loads in.

One of the options the server operator offered was to remove items from my inventory, and place them elsewhere, and then reset my player data (not a fun option), but moving the items elsewhere only took my regular inventory, not the contents of the backpack. We haven't done the user data deletion yet. How do we get at the contents?

Don't recall all of what is in my backpack, and don't want to lose it. Even the world owner seems unable to see the contents of it, so how can we even find out?

I tried having the owner turn off inventory retention, and to kill me at login, but the crash happens before my invulnerability wears off, and the pack doesn't drop.

Minecraft 1.21.4

Fabric Loader 0.16.14
I also tried another instance that used 0.16.10, also failed.

One of the versions of Traveler's Backpack that fails is 10.4.11, from this logged attempt. I think I've tried others, but don't recall which.

To reproduce, I login, and it crashes immediately. I don't even have time to open it to get it off.

Is there a way to remove it instantly, before any ticks pass?

I've added a couple of logs, but what else needs to be known to help this be fixed?

latest.log

crash-2025-05-18_02.01.56-client.txt

I have to fix this issue in an update, if you want I can provide mod build with this bug fixed so you can add it to your server and be able to play, before official update releases

Oh, gosh. How would they do that, and would all the server's users also need a bug fixed version?

Not really, you can install the updated mod on your pc and server, enter the game take off the magnet upgrade (at least for the time until official update releases) and then roll back to the previous version.

but if I think about it now, I might be able to release an update today, but not 100% sure

https://www.curseforge.com/minecraft/mc-mods/travelers-backpack-fabric
Fixed