Typescript Error ‘=’ expected. Cannot find name ‘unique’

Typescript Error ‘=’ expected. Cannot find name ‘unique’. Cannot find name ‘symbol’.
Ionic:

Ionic CLI : 5.4.1 (/usr/local/lib/node_modules/ionic)
Ionic Framework : ionic-angular 3.4.2
@ionic/app-scripts : 3.2.4

Cordova:

Cordova CLI : 9.0.0 ([email protected])
Cordova Platforms : none
Cordova Plugins : no whitelisted plugins (0 plugins total)

Utility:

cordova-res : not installed
native-run : 0.2.8 (update available: 1.0.0)

System:

NodeJS : v8.17.0 (/usr/bin/node)
npm : 6.13.4
OS : Linux 5.3

Source: New feed
Source Url Typescript Error ‘=’ expected. Cannot find name ‘unique’