Possible Fixes

Yes

Modpack Version

2.13

What happened?

This has also happened in 2.10 as well as other versions.
Everytime I know for sure this has happened I've been using the builder to build something. I'm not sure if it also happens when in mining mode. I also have not tested this with any other axe than an allthemodium axe. Though an older video shows it happening with another type of axe. Not sure if it happens with other items in that slot either.

Setup the builder to build something. Then with a axe in the third hotbar slot activate the builder and the axe instantly voids.

You can see this in action here where apparently this was an issue in ATM9:
https://www.reddit.com/r/allthemods/comments/1eggden/axe_disappeared/

latest.log

https://gist.github.com/ranmas/15e0f3a9bcb8f30292090d90e4b5ce02

Developer reports

No response