How to troubleshoot when Safari App Extension not appear in Safari Preferences?

Question

I'm developing a Safari App Extension. Previously it worked fine. When I run the project in Xcode, and enable Allow Unsigned Extensions in Safari, I can see my extension in Safari Preferences -> Extensions page.

After I merged code with one of my team member, suddenly the Extension cannot get installed.

I have tried:

• Clean the build folder in Xcode, and run again. But no luck.
• Restart Xcode doesn't help either.
• Use command pluginkit -mAvvv -p com.apple.Safari.extension to check installed Safari extensions list. My extension is not in the list.

There are some errors in Xcode output, but I can't link them with the issue I'm facing:

objc[49476]: Class AMSupportURLConnectionDelegate is implemented in both /System/Library/PrivateFrameworks/EmbeddedOSInstall.framework/Versions/A/EmbeddedOSInstall (0x7fff9a2aa748) and /System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x108db2600). One of the two will be used. Which one is undefined.
objc[49476]: Class AMSupportURLSession is implemented in both /System/Library/PrivateFrameworks/OSPersonalization.framework/Versions/A/OSPersonalization (0x7fff9b5d49f0) and /System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x108db2650). One of the two will be used. Which one is undefined.
2018-12-13 16:25:46.003099+0800 Safari[49476:1264277] Could not connect action, target class SecurityPreferences does not respond to -toggleJavaScriptCanOpenWindows:
2018-12-13 16:25:46.163130+0800 Safari[49476:1264277] AssertMacros: 0 (value = 0x0),  file: /BuildRoot/Library/Caches/com.apple.xbs/Sources/BiometricKit/BiometricKit-75.71.1/BiometricKit/BiometricKitXPCClient.m, line: 75
2018-12-13 16:25:46.163219+0800 Safari[49476:1264277] AssertMacros: 0 (value = 0x0),  file: /BuildRoot/Library/Caches/com.apple.xbs/Sources/BiometricKit/BiometricKit-75.71.1/BiometricKit/BiometricKitXPCClient.m, line: 396
2018-12-13 16:25:46.163465+0800 Safari[49476:1264277] [Framework-Internal-Legacy] AssertMacros: _xpcClient (value = 0x0),  file: /BuildRoot/Library/Caches/com.apple.xbs/Sources/BiometricKit/BiometricKit-75.71.1/BiometricKit/BiometricKit.m, line: 137
2018-12-13 16:25:47.060959+0800 Safari[49476:1264368] [RemotePlistController] The downloaded plist could not be loaded: Error Domain=NSCocoaErrorDomain Code=260 "The file couldn’t be opened because it doesn’t exist."
2018-12-13 16:25:47.128105+0800 Safari[49476:1264277] Scheduling the NSURLConnection loader is no longer supported.
2018-12-13 16:25:47.491811+0800 Safari[49476:1264370] NSURLConnection finished with error - code -1100
2018-12-13 16:25:47.799590+0800 Safari[49476:1264514] [CloudBookmarks] Error fetching remote migration state: Error Domain=com.apple.SafariBookmarksSync.CloudBookmarksErrorDomain Code=0 "(null)"
2018-12-13 16:25:47.953259+0800 Safari[49476:1264277] [WebKit2Callbacks] Page (pid: 0) did become unresponsive
2018-12-13 16:25:47.970927+0800 Safari[49476:1264512] NSURLConnection finished with error - code -1100
2018-12-13 16:25:48.032647+0800 Safari[49476:1264425] [RemotePlistController] The downloaded plist could not be loaded: Error Domain=NSCocoaErrorDomain Code=260 "The file couldn’t be opened because it doesn’t exist."
2018-12-13 16:25:48.125530+0800 Safari[49476:1264426] Calling IOPPFGetProperty simulator_utility_clamp!
2018-12-13 16:25:48.840769+0800 Safari[49476:1264277] [WebKit2Callbacks] Page (pid: 49481) did become responsive

Now I'm running out of options. It lacks official documentation in Apple Developer site.

Is there regular steps to troubleshoot this kind of issue? Is there any kind of system logs which can help me address the error? Any suggestion is appreciated.

Answer 1

Make sure that the extension .appex is listed as embedded content for your App Extension target. Otherwise it doesn't get bundled when you build from Xcode. Look in the project editor under Target_Name > General > Frameworks, Libraries and Embedded Content. The extension should be listed there.

Also check under the Build Phases tab > Dependencies that your extension is added there as well.