will items disappear in minecraft if the player didn't pick them up for very long time

In Minecraft, items do not disappear automatically if left uncollected for a long time. However, there are certain conditions under which items can be lost:

1. Entity Despawning: If an item is dropped by a mob and the mob despawns, the item will eventually despawn after a certain amount of time, typically 5 minutes.
2. Chunk Unloading: Items in unloaded chunks (areas of the world that are not currently being rendered or are not within the player's vicinity) may be removed from the game to save memory.
3. Game Update: If you're playing on a multiplayer server and the server resets or updates, items might be lost if they haven't been collected.
4. World Corruption: In rare cases, bugs or glitches could lead to items being lost.

Items dropped by players or placed in containers, such as chests or barrels, do not despawn unless the container is destroyed or the items are taken out. Always ensure you collect important items promptly to avoid losing them due to these factors.