Hi, Is it possible to use the iOS26 Liquid Glass icon on iOS 26 (built with Icon Composer), and use the old icon on iOS18 devices? I imported the icon file into my Xcode project and it seems to use the new icon on iOS18 (and earlier) devices as well. Thanks.
You can pass --enable-icon-stack-fallback-generation=disabled as a flag to the asset catalog compiler. Go to project -> Your target -> Build Settings -> Search for "Asset Catalog" -> Add the mentioned flag in Asset Catalog Other Flags. In this case versions prior to 26 will continue to use the previous app icons.
However for my project this caused problems when uploading to App Store Connect apparently due to missing png icon files. This has never been a problem before and the app seems to be displayed with the correct app icons at all times. I am also using alternative app icons. I am yet to further investigate this to file a good feedback report.