I'm trying to add an iMessage extension to my app, and upon adding the iMessage App Icon set, I ran into an issue with one specific icon size: 1024x768px, aka 1x 1024x768pt. When I remove this one icon from the icon set, it compiles and runs fine, however I can't push it to the App Store as I get the error: "Asset validation failed. Missing Image Asset. Your app is missing the Large App Icon asset 'AppIcon' in 'Payload/Runner.app/PlugIns/MessagesExtension.appex'." I'm assuming this refers to 1024x768px, as this size placeholder appears upon adding a New Messages Extension Icon to my assets folder, and 1024x1024 is already included and compiles fine with it. However, when I add the 1024x768 icon, and try to run the app, I get the error: "Command CompileAssetCatalog failed with a nonzero exit code" The app icon's filename is correct, it is exactly 1024x768 px, and my contents.json correctly includes : { "filename" : "AppIcon_1024x768.png", "idiom" : "ios-marketing", "platform" : "ios", "scale" : "1x", "size" : "1024x768" } as is the same format for all of my other icons that work. Why am I running into this issue upon inclusion of this one required size? How do I fix it?