When submitting my macOS app with Safari Web Extension for App Store review, I am getting Rejections due to the extension not installing onto the Safari browser on the tester's device. I've reproduced this by performing the following steps, but I have no idea what I need to do differently to resolve the issue: Build a new Archive of the app via Xcode In Organizer, click Distribute App -> App Store Connect -> Export Run the .pkg installer created by the Export Run the app Open Safari 14 Select Develop -> Allow Unsigned Extensions Expectation: Safari Extensions list includes my extension Actual: My extension is completely missing from the list I reproduced the same issue following the same exact steps using the Sea Creator project on Apple's documentation (https://developer.apple.com/documentation/safariservices/safari_web_extensions/developing_a_safari_web_extension). To reiterate, I am unsure of how come my app is not installing the extension to Safari. The .appex is contained in my .app as expected, and I have Embed without Signing (as opposed to Do not Embed) selected for the Safari Web Extension in the app target. Any and all guidance and insights would be greatly appreciated. And, yes, I replied to the App Store review but I suspect other developers may be running into this issue themselves and may have solutions to offer.