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Issue description:

Players can duplicate a full chest of items with personal chests.
Note: This issue doesn't really work on singleplayer, seems to only work if there is enough delay to not instantly open the GUI (lagspike or slowish server)

Steps to reproduce:

1. Get two personal chests in your hotbar.
2. Fill the first one with items.
3. Exit GUI
4. Right click chest with items but quickly swap to the other one with number keys or scroll before GUI opens.
5. Your second chest is now a copy of the first one. Take items out of this and it will not affect the first.

Version (make sure you are on the latest version before reporting):

Forge: forge-1.12.2-14.23.3.2655-universal
Mekanism: Mekanism-1.12.2-9.4.5.340
Other relevant version:

If a (crash)log is relevant for this issue, link it here: (It's not)

[gist/pastebin/etc link here]

Bump, this is still a very present and major issue that ruins the economy on any server running mekanism.

@Blayyke I'm not a dev, but could you test the dupe on Mekanism-1.12.2-9.4.13.349 and forge-1.12.2-14.23.5.2807?
The dupe doesn't seem to work on those versions. However, on Mekanism-1.12.2-9.4.13.349 and forge-1.12.2-14.23.5.2768 the dupe works.

I just want to make sure the dupe is patched on the latest version and that it's not just me messing up.

After doing some more testing I was able to get it to work once on Mekanism-1.12.2-9.4.13.349 and forge-1.12.2-14.23.5.2807.

Hm, seems I cannot reproduce with a later version of mekanism. Closing.