I have had a few rejects of edits which improved formatting of code blocks on the basis that the improvement was minor.
Looking at the representation of the edit in both 'rendered output' and 'markdown', it is difficult to visualize the actual formatting improvement as it would display in the question or answer.
I suspect that other formatting improvements may also be difficult to visualize, and are not supported by the render output (like color coding of code). Other posts have suggested that the diff markup in certain instances makes it difficult to visualize the changes.
Would it not be beneficial to add an additional view 'actual display' rendering the before and after as it would display?
That way if it is not immediately apparent to the reviewer the benefit of the edit, they can check the actual display to make sure that there indeed is no benefit.