Hi there, I know that Autofilter is to blame here but I wanted to post this here so that you were aware of the issue in case there could be anything done for your mod to harden against a crash like this in the future.

https://gist.github.com/jarquafelmu/896412920dbed2a96f6be85a36f0aecb

With the mod autofilter and deadlock's stacked items on a belt, trying to upgrade the belt causes this crash to happen

The deadlock stacked item has nothing to do with it. Recreated the error without the mod loaded.

Also, this happens with upgrading power poles as well. Something might be fishy with the on_built_entity event Upgrade Planner raises... This should not be grabbed by Autofilter, since I am filtering the event for inserters.

Fixed in Autofilter 0.18.4.

Thanks for the information. I'll look into what's up with the event.

Someone in the Factorio Discord pointed me to the fact that it is fishy by design. Event filters do not apply to mod-raised events, so there is no bug on your side :)

Huh interesting good to know.