Xcode BoringSSL peer disconnect causing app to hang on startup - ios

Question

Recently I started getting inconsistent BoringSSL issues that is causing my cordova/ionic app to hang. It happens about 1 out of every 4 or 5 times I launch the app from Xcode to a physically attached test iPhone 6. The test phone uses WiFi only (no carrier network). Having a devil of a time find any solid solutions or what the root of the problem is.
Some indicate its DNS, others say its related to Firebase...I have tried a few of the fixes those threads have mentioned but none are working for me.
[BoringSSL] nw_protocol_boringssl_input_finished(1543) [C3.1:2][0x12fd335c0] Peer disconnected during the middle of a handshake. Sending errSSLClosedNoNotify(-9816) alert
TIC TCP Conn Failed [3:0x2805712c0]: 3:-9816 Err(-9816)
[BoringSSL] nw_protocol_boringssl_input_finished(1543) [C5.1:2][0x12fe46470] Peer disconnected during the middle of a handshake. Sending errSSLClosedNoNotify(-9816) alert
TIC TCP Conn Failed [5:0x280575f80]: 3:-9816 Err(-9816)
[BoringSSL] boringssl_context_alert_callback_handler(3724) [C6.1:2][0x12fd43710] Alert level: fatal, description: inappropriate fallback
[BoringSSL] boringssl_session_errorlog(224) [C6.1:2][0x12fd43710] [boringssl_session_handshake_incomplete] SSL_ERROR_SSL(1): operation failed within the library
[BoringSSL] boringssl_session_handshake_error_print(205) [C6.1:2][0x12fd43710] 5097281768:error:1000043e:SSL routines:OPENSSL_internal:TLSV1_ALERT_INAPPROPRIATE_FALLBACK:/BuildRoot/Library/Caches/com.apple.xbs/Sources/boringssl/boringssl-109.250.2/ssl/tls_record.cc:586:SSL alert number 86
[BoringSSL] boringssl_context_get_error_code(3617) [C6.1:2][0x12fd43710] SSL_AD_INAPPROPRIATE_FALLBACK
TIC TCP Conn Failed [6:0x280576640]: 3:-9860 Err(-9860)
NSURLSession/NSURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9860)
Task <02ADA890-35C5-4DE7-B0E5-6EC812CF79E6>.<1> HTTP load failed (error code: -1200 [3:-9860])
Task <02ADA890-35C5-4DE7-B0E5-6EC812CF79E6>.<1> finished with error - code: -1200
nw_protocol_boringssl_get_output_frames(1301) [C1.1:2][0x12fe15ea0] get output frames failed, state 8196
nw_protocol_boringssl_get_output_frames(1301) [C1.1:2][0x12fe15ea0] get output frames failed, state 8196
If the app sees this error when initializing, the app hangs at the splash screen. If it makes it past this issue then the app works just fine and I only see nw_protocol_get_output_frames messages every so often (don't know what those are about either).
Anyone have any ideas as to what is causing this, where to look or possibly what the fix is?
Cordova CLI: 9.0.0 (cordova-lib#9.0.1)
cordova-ios: v5.0.0
Gulp version: CLI version 3.9.1
Gulp local:
Ionic Framework Version: 1.3.4
Ionic CLI Version: 1.7.16
Ionic App Lib Version: 0.7.3
ios-deploy version: 1.9.4
ios-sim version: 8.0.1
OS: Mac OS X El Capitan
Node Version: v6.11.4
Xcode version: Xcode 10.1 Build version 10B61

Answer 1

I was stuck at this error and what I did was enable all kinds of logs on XCode and that revealed that the error with this BoringSSL was from a call to the API Crashlytics of google. What solved this matter to me was enter on firebase, enable crashlytics for my project, install the plugin (https://ionicframework.com/docs/native/firebase-crashlytics) and initialise it.
To find crashlytics on firebase you enter on the console and search on the left, under the menu quality, crashlytics. After that if you have already your GoogleService-Info.plist on your app, what remains is to install the plugin and initialise it according the docs.
[EDIT] Dont know if the above will contribute, because on another batch of tests I found that it didnt fix the issue. But when I add the next lines to config.plist it resolves:
<key>NSAppTransportSecurity</key>
<dict>
<key>NSExceptionDomains</key>
<dict>
<key>app-measurement.com</key>
<dict>
<key>NSIncludesSubdomains</key>
<true/>
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<true/>
<key>NSExceptionRequiresForwardSecrecy</key>
<false/>
</dict>
<key>mtalk.google.com</key>
<dict>
<key>NSIncludesSubdomains</key>
<true/>
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<true/>
<key>NSExceptionRequiresForwardSecrecy</key>
<false/>
</dict>
<key>play.googleapis.com</key>
<dict>
<key>NSIncludesSubdomains</key>
<true/>
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<true/>
<key>NSExceptionRequiresForwardSecrecy</key>
<false/>
</dict>
<key>settings.crashlytics.com</key>
<dict>
<key>NSIncludesSubdomains</key>
<true/>
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<true/>
<key>NSExceptionRequiresForwardSecrecy</key>
<false/>
</dict>
<key>googleapis.com</key>
<dict>
<key>NSIncludesSubdomains</key>
<true/>
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<true/>
<key>NSExceptionRequiresForwardSecrecy</key>
<false/>
</dict>
<key>localhost</key>
<dict>
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<true/>
</dict>
<key>127.0.0.1</key>
<dict>
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<true/>
</dict>
</dict>
<key>NSAllowsArbitraryLoadsInWebContent</key>
<false/>
</dict>
https://forums.developer.apple.com/thread/42555
https://cocoacasts.com/app-transport-security-has-blocked-my-request