What is the proper way to modify the flags? I would like English to use the US flag and Spanish to use the Mexican flag. I'm using the enterprise WordPress plugin. I see 16.png, 24.png, and 32.png. Should I modify those files or is there a different way to do it?
The previous developer already replaced the UK flag with US flag but those three png files are unmodified so I don't know how they did it.