Minecraft Version

1.21.1

Immersive Engineering Version

ImmersiveEngineering-1.21.1-12.0.0-182

Expected Behavior

1. A wooden storage crate is obtained
2. Items put into crate
3. Hammer is used to seal the crate
4. Crate is picked up
5. Crate is placed down
6. Items put into the crate are still there

Actual Behavior

1. A wooden storage crate is obtained
2. Items put into crate
3. Hammer is used to seal the crate
4. Crate is picked up (and tool tip shows contents of crate)
5. Crate is placed down
6. No items exist in the crate

Steps to reproduce

1. In creative, give a wooden storage crate, 64 oak logs, and a hammer
2. Please wooden storage crate down
3. Put in 64 oaks logs
4. Break storage crate with axe or fist
5. View item crate in inventory to confirm contents exist within crate
6. Place wooden crate back down
7. Open item crate and see there are no contents

Debug Crash Log

https://pastebin.com/NGzfp6iZ

When was the point you exited creative mode. There Were issues with switching Modes while having stuff inthe toolbox that vanished too

I am having the same problem, but nothing about creative mode.

1. I crafted a crate and placed items inside it.
2. Used the hammer to close it. Broke the crate.
3. When I picked it up, I could see the items inside of it.
4. When I placed it down, there were no items inside.

same issue here on All the Mods 10 pack (v1.7) - found the crates in engineer's house - sealed them with hammer after placing items inside, picked up crate. Items can be seen in crate when mousing over in my inventory but are then deleted when the crate is placed down.