ionic splashscreen gives ERR_CONNECTION_REFUSED on older android - ionic-framework

Question

After I package build my release using the Ionic Pro service, download it, and install it on a Android 4.4.2 device, I get an alert right over the splashscreen titled: "Application Error", with the following error:
net::ERR_CONNECTION_REFUSED (http://localhjost:8080/)
After a while the splashscreen dissapears and a white page says: "Webpage not available:"
Screenshot
It runs fine on another device, running Android 8.0.0.
What could cause this error and how do I fix it?

Answer 1

Downgrade your cordova-plugin-webview to 1.2.1, because version 2.x.x using http:// protocol instead of file://
https://ionic.zone/debug/ionic-and-android-4

Answer 2

Most of the people will suggest you to add to your config.xml the following line
<allow-intent href="http://localhost:<YOUR_PORT_HERE>/*" />
You already have this , so the above line is useless
<allow-intent href="http://*/*" />
<allow-intent href="https://*/*" />
<allow-intent href="tel:*" />
<allow-intent href="sms:*" />
<allow-intent href="mailto:*" />
<allow-intent href="geo:*" />
Some users will suggest you to downgrade the cordova-plugin-ionic-webview plugin to to 2.1.2 version, for some users work for others not.
What i suggest you to do in your package.json file, add this to your
cordova-plugin-ionic-webview
from:
"cordova": {
"plugins": {
"cordova-plugin-ionic-webview": {}
},
to:
"cordova": {
"plugins": {
"cordova-plugin-ionic-webview": {
"ANDROID_SUPPORT_ANNOTATIONS_VERSION": "27.+"
}
},