I apologize in advance that this is not the proper bug report format, but this is a pretty big bug and I'm sure it's happened to a lot of people, and quite frankly I don't think a forge log would help this issue.

 

Forge version: 9.10.0.804 (this bug happens in almost every version from what I know)

 

This glitch happens in FTB modpack, void's wrath modpack, Voltz modpack, Galacticraft, and many, many more. I'm assuming it happens no matter what mods are installed, but these are the mods I've used, and it's happened in all of them.

 

The bug is, when you die, break a chest, or explode something; not all of the entities that should drop, appear. I know a lot of people have experienced this glitch, and it's very weird because it doesn't happen all the time. Also, I know some people may think "You're an idiot, the entities just flew somewhere and you couldn't find them" This is false, I've killed myself in the middle of open plains and in superflat and it still happens. Let me know if anyone else experiences this.

It all depends on what items are spawning and how.

If a mod you're using screws with the drops then it's probably doing something wrong.

Forge itself does very little when it comes to the drops.

If you can provide exact steps to reproduce that'd be good.

 

You need to be careful with explosions as items only have 1 health and will die when ANYTHING hurts them. Including the explosion.

Also remember that entity items will collect themselves into a single entity if they can stack. So you may not see say.. 5 blocks floating on the ground you may just see one with a stack size of 5.