The base messages extension template builds but won't install or load

I am on a fresh install of Xcode 15.3 on macOS 14.4 (23E214). I created an iMessage App template and signed it with my personal team's certificate. When I click the run button, it successfully builds and opens the simulator to the Messages app but does not open the compact extension view (or install the extension such that it shows up in the More messages extension list). This reproduces on my older laptop (same version of Xcode) as well as my friend's (also same version of Xcode).

Of note:

  • The IceCreamBuilder app installs and runs correctly with no modifications
  • I have not provided any icons for the messages extension
  • The iMessage App template comes with an empty main app that does not install on the home screen

The only console output that seems to differ from when I run the IceCreamBuilder is this message, which appears after a couple seconds of running the project:

unhandled process MobileSMS
Type: Error | Timestamp: 2024-03-09 00:41:07.763631-05:00 | Process: MobileSMS | Library: CoreParsec | Subsystem: com.apple.parsec | Category: CoreParsec | TID: 0xff097

My friend figured out a fix:

  1. Create a new scheme for the base app (not the extension)
  2. Build and run that scheme (it'll show an error dialog and not do anything)
  3. You should now be able to run the extension as expected

This seems like an actual bug with the project template so I'd be happy to elevate this ticket if possible.

It seems like changes to the extension won't be propagated to the test device/simulator unless you rerun the main app target. I figure this means the MessagesExtension scheme is bugged?

Having the same issue since updating to 15.3. I wonder if it's specific to cases (like mine) where the main app is just an empty container that holds the extension (you can't run it directly) Is there perhaps a way to configure the run scheme to build and deploy the main target app before running the messages extension? I've been trying but without success

Not a solution, but I downgraded to Xcode 15.0 and it works again.

iMessages Apps work in 15.2 work as well, it reports the same errors as 15.3 and 15.4, but the app eventually launches in the simulator. 15.3 and 15.4, both result in numerous errors in the simulator and then the app not launching.

Just tried 16 beta 2. It's broken in the same way as 15.3. This has made the workflow for developing message extensions almost impossible because i keep forgetting to do the extra of switching the scheme to run the base app, waiting for it to time out and then switching the scheme back to the message extension... and even worse it will happily execute the older build of the extension, so it's not always obvious that it didn't update.

Our engineering teams 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 XX_NECESSARY_INFO_1 and XX_NECESSARY_INFO_2, and post the FB number here once you do. Bug Reporting: How and Why? has tips on creating your bug report.

I am on Xcode 16 Beta 5 and it is now installing and launching on the Simulator running iOS 18, but it still does not install or launch on a Physical Device on iOS 17.5.

The base messages extension template builds but won't install or load
 
 
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