I tried to bring this bug to the attention of the exile developers, but they didn't seem to buy it.
This video was an intitial test of the bug on our test server after the player had brought it to our attention. At the time, we made several incorrect assumptions regarding the limitations of the bug. It does not matter what size, color, or type the backpacks are.
https://youtu.be/L8YjJi3o0xg