Hello, my problem is I glitched a backpack into another backpack and I can't take out that backpack.
It happened when I opened the backpack and pressed 9 (in the 9th slot I have another backpack). But when I tried to repeat, it doesn't glitched.
I can get back my items using NBT Explorer. I think you should create a config what can enable moving the backpack when a backpack GUI is open.

• IronBackpacks: 3.0.4
• Minecraft: 1.12.2
• Forge: 14.23.1.2601

Sorry for bad English, I'm hungarian.

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