Is your feature request related to a problem? Please describe.
I use Hopper Gadgetry extensively: https://www.curseforge.com/minecraft/mc-mods/hopper-gadgetry
And they use "Grated Hoppers" which are basically hoppers with a filter and the backpacks don't work with those.

Describe the solution you'd like
Add the functionality that items be retrieved from the backpacks by grated hoppers please.

Describe alternatives you've considered
So far, I need to replace them with normal hoppers. Not ideal for existing builds.

Thank you.

This turns out to be a bug on Fusz end, since I have talked to him about it. Feel free to close the issue.

Thank you.