crop region persists when changing single cell / full field

[toloudis]

Description

Cropped region persists with changing file and even with changing from "Single Cell" to "Full Field" - it's nice and maybe useful for file changes (consistent data size) but not sure for cell>field changes

Expected Behavior

Could keep crop region when completely switching image, but should not keep when switching singlecell/fullfield.
We want to remember the crop region for both single cell and full field but should not keep same crop region when switching.
Also see #176

Reproduction

A minimal example that exhibits the behavior.

Environment

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