If a player who is not the owner of a claim attempts to place a block/shulker/etc in a claim the placement fails as expected, but the block being placed gets removed from the player's inventory (while in survival). This is very unexpected for someone who doesn't know they are in a claim who then accidentally loses an expensive block or a shulker box full of valuables.

Using Modrinth with Fabric loader 0.15.9, Minecraft 1.20.4, and GOML 1.11.0+1.20.3-rc1

I looked through existing bugs but didn't see anything similar.

Is it real removal or just desync (client thinks it's gone, but it's still there if you place it elsewhere/throw it out)?

Ah. Yes. I can throw it and move it with the mouse. Was just testing out the mod and didn't check that. Thanks!