No
That's not what I imagine, I imagine time to be the same as proposed by Einstein. In that theory, we all constantly move forwards through time at the speed of light, but this motion is a vector shared by our speed through space, so the faster you move through space, the slower you move through time (to an external observer).
Your question is a category error because in essence it is 'imagine an impossible thing, what would happen in the real world if this impossible thing existed'. My answer is that there would be something akin to an event horizon inside the box, just like happens in the only place we know of in the real world where time stops, at the edge of a black hole. The contents would vanish and never interact with our universe again.
Your 'magic box' is only sealed in 3 dimensions, there are quite a few more than that. There is also more than one way to conceptualise time stopping. One is how you imagine it, where you continue to move forwards through time at the speed of light, but your internal clock stops. The other way is that your internal clock does not stop, but you do not move forwards through time while the rest of the universe does.
Imagine it this way, you have created a volume where anything placed in it remains at the point in time and space where+when it was placed inside. When we move on, and it is now 1 second later, where is the onion? It exists 1 second ago, and we cannot see it, to us, it simply vanishes.
Mind your fingers putting the onion in.
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My Name was saying these words inside your head on, Sun 21 Jan 2024, 10:47,
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