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Can the upload only be in msix package format?
The Packages page page of the app submission process is where you upload all of the package files (.msix, .msixupload, .msixbundle, .appx, .appxupload, and/or .appxbundle) for the app that you're submitting. Please check: Upload app packages.
Can I upload only the difference content to be updated?
No, you can't
Is there any way to exceed 25g?
No, currently, the store won't accept apps bigger than 25g. Please check: Package format requirements
When the player is updating, is it the whole package update or the differential update?
It is whole package update.
Thank you.
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