I have made appx file, i have tested on Windows App Certification Kit Toolkit and also installing extension in windows 10 running properly, but when I publish the extension to the Store, it gives me this error:
"App Policies: 10.1.1 Extensions
Notes To Developer
Apps that claim to be an extension must clearly identify the app for which they are an extension"
I have given a description in the json and appx files and also in windows dev partner, but it's still giving the same error in certification.