JavaScript errors in Google Search Console - Babel

#1

Ionic:

ionic (Ionic CLI) : 4.11.0 (C:\Users…\AppData\Roaming\npm\node_modules\ionic)
Ionic Framework : @ionic/angular 4.1.0-dev.201902142010.08fe8e4
@angular-devkit/build-angular : 0.12.2
@angular-devkit/schematics : 7.1.4
@angular/cli : 7.1.4
@ionic/angular-toolkit : 1.2.2

Cordova:

cordova (Cordova CLI) : not installed
Cordova Platforms : android 7.1.4, browser 5.0.4, ios 4.5.5
Cordova Plugins : cordova-plugin-ionic-keyboard 2.1.3, cordova-plugin-ionic-webview 2.3.2, (and 10 other plugins)

System:

Android SDK Tools : 26.1.1 (C:\Users…\AppData\Local\Android\Sdk)
NodeJS : v10.15.1 (C:\Program Files\nodejs\node.exe)
npm : 6.4.1
OS : Windows 10
Hi,
I have built an Ionic 4 PWA and I would like to get the entire PWA crawled by Google.

I am getting the following JavaScript errors in Google Search Console:
JavaScript Error:
Uncaught ReferenceError: Proxy is not defined
https://www.dummyurl.com.au/main.b21f4c0bb35253bff972.js:1
t
https://www.dummyurl.com.au/main.b21f4c0bb35253bff972.js:1:447806
push.gcOT
https://www.dummyurl.com.au/main.b21f4c0bb35253bff972.js:1:447697
r
https://www.dummyurl.com.au/runtime.b0d99aaff5872ed51c46.js:1:507
push.zUnb
https://www.dummyurl.com.au/main.b21f4c0bb35253bff972.js:1:557039
r
https://www.dummyurl.com.au/runtime.b0d99aaff5872ed51c46.js:1:507
push.0
https://www.dummyurl.com.au/main.b21f4c0bb35253bff972.js:1:507
r
https://www.dummyurl.com.au/runtime.b0d99aaff5872ed51c46.js:1:507
f
https://www.dummyurl.com.au/runtime.b0d99aaff5872ed51c46.js:1:376
a
https://www.dummyurl.com.au/runtime.b0d99aaff5872ed51c46.js:1:248
(anonymous function)
https://www.dummyurl.com.au/main.b21f4c0bb35253bff972.js:1:47

Has anyone come across this problem before? It looks to be a Babel problem:


Any assistance would be appreciated.

#2

Found the solution:

“Googlebot is stuck on Chrome 41, which lacks support for many modern JavaScript features. SPA and library authors haven’t escaped the legacy browsers yet.”

The Proxy feature in JavaScript is not supported so it looks like I will now be spending some time setting up Server Side Rendering.