In a larger context I resorted back to creating a blank project and running my build commands.
Same error:
ionic start myApp blank
cd myApp
ionic cordova run ios --debug --target="iPhone-8" --consolelogs
ionic-app-scripts build --target cordova --platform ios
[11:39:29] ionic-app-scripts 3.2.0
[11:39:29] build dev started ...
[11:39:30] clean started ...
[11:39:30] clean finished in 1 ms
[11:39:30] copy started ...
[11:39:30] deeplinks started ...
[11:39:30] deeplinks finished in 15 ms
[11:39:30] transpile started ...
[11:39:33] transpile finished in 3.16 s
[11:39:33] preprocess started ...
[11:39:33] preprocess finished in 1 ms
[11:39:33] webpack started ...
[11:39:33] copy finished in 3.31 s
[11:39:37] webpack finished in 4.35 s
[11:39:37] sass started ...
[11:39:38] sass finished in 1.27 s
[11:39:38] postprocess started ...
[11:39:38] postprocess finished in 10 ms
[11:39:38] lint started ...
[11:39:38] build dev finished in 8.92 s
[11:39:41] lint finished in 2.65 s
> cordova run ios --debug --target iPhone-8
Building for iPhone 8 Simulator
Building project: /myApp/platforms/ios/myApp.xcworkspace
Configuration: Debug
Platform: emulator
Build settings from command line:
CONFIGURATION_BUILD_DIR =
/myApp/platforms/ios/build/emulator
SDKROOT = iphonesimulator12.0
SHARED_PRECOMPS_DIR =
/myApp/platforms/ios/build/sharedpch
Build settings from configuration file '
/myApp/platforms/ios/cordova/build-debug.xcconfig':
CLANG_ALLOW_NON_MODULAR_INCLUDES_IN_FRAMEWORK_MODULES = YES
CODE_SIGN_ENTITLEMENTS = $(PROJECT_DIR)/$(PROJECT_NAME)/Entitlements-$(CONFIGURATION).plist
CODE_SIGN_IDENTITY = iPhone Developer
ENABLE_BITCODE = NO
GCC_PREPROCESSOR_DEFINITIONS = DEBUG=1
HEADER_SEARCH_PATHS = "$(TARGET_BUILD_DIR)/usr/local/lib/include" "$(OBJROOT)/UninstalledProducts/include" "$(OBJROOT)/UninstalledProducts/$(PLATFORM_NAME)/include" "$(BUILT_PRODUCTS_DIR)"
OTHER_LDFLAGS = -ObjC
SWIFT_OBJC_BRIDGING_HEADER = $(PROJECT_DIR)/$(PROJECT_NAME)/Bridging-Header.h
/myApp/platforms/ios/build/emulator/myApp.app/Info.plist file not found.
[ERROR] An error occurred while running subprocess cordova.
cordova run ios --debug --target iPhone-8 exited with exit code 1.
Re-running this command with the --verbose flag may provide more
information.
ionic --version
4.1.2
cordova --version
8.0.0 & @latest 8.1.1
XCode Version 10.0 (10A255) + build tools
macOS 10.13.6 - High Sierra. Mojave on a different machine fails the same.
-------------- FIX --------------
This is how I got it back up to do livereload without the bugs:
ionic cordova platform remove ios
sudo npm install -g ionic@3.20.0
ionic cordova platform add ios
open platform/ios/MyApp.xcworkspace
Follow instructions to fall back to XCode legacy build system as on
Run my build script as before, without the --buildFlag='-UseModernBuildSystem=0'