It is called the DROSTE EFFECT.
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The original 1904 Droste cocoa tin, designed by Jan Musset (1861–1931)[a]
The Droste effect (Dutch pronunciation: [ˈdrɔstə]), known in art as an example of mise en abyme, is the effect of a picture recursively appearing within itself, in a place where a similar picture would realistically be expected to appear. This produces a loop which mathematically could go on forever, but in practice only continues as far as the image's resolution allows.