The red cross on the flag is a traditional symbol of the region, and the French flag in the upper left corner indicates it is a French territory. You could say it's an emoji that shows the harmony of two cultures.

Although this flag is not the official one, it is widely used as it best represents the identity of the region. The French flag is used at official events. In this way, emojis capture not only official symbols but also the unofficial ones that a community uses to express itself.