After updating to iOS 5.1.1 from 4.5.2 , can't proceed more splash image

Ionic Framework ionic-v3
1

I had a New apps that use UIWebView are no longer accepted problem
so I added some value like below to config.xml and then update to 5.1.1. iOS version.
and when I downgrade to 4.5.2, then UIWebView problem is caused

but when I build iOS app to my phone, it has only splash image loading and have below error on Xcode

2020-05-02 01:06:14.645701+0900 Ming[2139:1102793] Apache Cordova native platform version 5.1.1 is starting.
2020-05-02 01:06:14.645810+0900 Ming[2139:1102793] Multi-tasking -> Device: YES, App: YES
2020-05-02 01:06:14.657386+0900 Ming[2139:1102793] [CDVTimer][console] 0.046015ms
2020-05-02 01:06:14.657553+0900 Ming[2139:1102793] [CDVTimer][handleopenurl] 0.046015ms
2020-05-02 01:06:14.658941+0900 Ming[2139:1102793] Unlimited access to network resources
2020-05-02 01:06:14.659135+0900 Ming[2139:1102793] [CDVTimer][intentandnavigationfilter] 1.417994ms
2020-05-02 01:06:14.659304+0900 Ming[2139:1102793] [CDVTimer][gesturehandler] 0.048041ms
2020-05-02 01:06:14.659477+0900 Ming[2139:1102793] [CDVTimer][inappbrowser] 0.064015ms
2020-05-02 01:06:14.659670+0900 Ming[2139:1102793] CDVIonicKeyboard: resize mode 1
2020-05-02 01:06:14.665143+0900 Ming[2139:1102793] CDVIonicKeyboard: WARNING!!: Keyboard plugin works better with WK
2020-05-02 01:06:14.665292+0900 Ming[2139:1102793] [CDVTimer][cdvionickeyboard] 5.670905ms
2020-05-02 01:06:14.678984+0900 Ming[2139:1102793] [CDVTimer][splashscreen] 13.647914ms
2020-05-02 01:06:14.690095+0900 Ming[2139:1102793] [CDVTimer][statusbar] 10.983944ms
2020-05-02 01:06:14.690243+0900 Ming[2139:1102793] [CDVTimer][uniquedeviceid] 0.060081ms
2020-05-02 01:06:14.690282+0900 Ming[2139:1102793] [CDVTimer][TotalPluginStartup] 32.966018ms
2020-05-02 01:06:14.735415+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.735982+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.736134+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.738397+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.761585+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.787764+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.787877+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.799145+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.799197+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.807666+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.807739+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.807770+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.807951+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.808091+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.812788+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.812853+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.813081+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.813177+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.813206+0900 Ming[2139:1102793] [Process] kill() returned unexpected error 1
2020-05-02 01:06:14.915087+0900 Ming[2139:1102793] [ProcessSuspension] 0x10a2e5500 - ProcessAssertion::processAssertionWasInvalidated()
2020-05-02 01:06:14.928310+0900 Ming[2139:1102793] [ProcessSuspension] 0x10a2e5560 - ProcessAssertion::processAssertionWasInvalidated()
2020-05-02 01:06:15.047080+0900 Ming[2139:1102960] Request <OSRequestRegisterUser: 0x2810df330> success result {
    id = "2e4e9359-4628-4c3f-9363-c48172297272";
    success = 1;
}

myconfig.xml is as below

<preference name="WKWebViewOnly" value="true" />
<allow-navigation href="http://localhost:8080/*" />
<preference name="AutoHideSplashScreen" value="true" />
<feature name="CDVWKWebViewEngine">
    <param name="ios-package" value="CDVWKWebViewEngine" />
</feature>
<preference name="CordovaWebViewEngine" value="CDVUIWebViewEngine" />
2

Doesn’t look like you have a WKWebView plugin installed.

cordova plugin add cordova-plugin-ionic-webview