In 2017 a Wikimedia Commons user changed the inside of the tiara to red because that’s how it appears on the Vatican Coat of Arms. But this assumption turned out to be faulty, because the official flag spec sheet uses different colors than the Coat of Arms. The mistake was quickly noticed by an anonymous IP who wrote an extensive and well-researched explanation of the error on the file’s talk page. Unfortunately, nobody read it, and the mistake lived on for 5 years before another user noticed it and reverted the file.
“A very compact representation of an image placeholder. Store it inline with your data and show it while the real image is loading for a smoother loading experience.”