I created a standalone iMessage app using Xcode template as the below:
I didn't change a single line of code except just populating all necessary icons. After installing the extension using Xcode, nothing showed up in the iMessage. Did I miss anything? I've been stuck here for many hours.
Plug your app into Console.app and filter by the process for your Messages App (target name). This should provide additional context. If you are still having the issue or cannot pinpoint it, our engineering teams will need to investigate this issue, as resolution may involve changes to Apple's software. I'd greatly appreciate it if you could open a bug report, include a sysdiagnose and sample project, and post the FB number here once you do. Bug Reporting: How and Why? has tips on creating your bug report.
Rico WWDR - DTS - Software Engineer