I attached a second screenshot. It's far away from being a high quality comparison screen but the mockup was a low quality screen and I tried to show the checkbox in the mockup and the checkbox in the current implementation at the same size and with a large zoom to demonstrate the difference in spacing around the checkmark.
Bug 1708888 Comment 1 Edit History
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I attached a second screenshot. It's far away from being a high quality comparison screen but the mockup was a low quality screen and I tried to show the checkbox in the mockup and the checkbox in the current implementation at the same size and with a large zoom to demonstrate the difference in spacing around the checkmark (top: mockup, bottom: implementation).