Q:

Unexpected provider when downgrading Angular component to AngularJS

I've managed to successfully bootstrap my hybrid app, but as soon as I try to use a downgraded Angular component directive in my AngularJS template I'm getting this error:
Error: StaticInjectorError[{providers:[[object Object]], parent:[object Object], name:"DowngradeComponentAdapter"}]: Unexpected provider
    at staticError (core.js:1360)
    at recursivelyProcessProviders (core.js:1209)
    at new StaticInjector (core.js:1079)
    at Function.webpackJsonp../node_modules/@angular/core/esm5/core.js.Injector.create (core.js:1051)
    at DowngradeComponentAdapter.webpackJsonp../node_modules/@angular/upgrade/esm5/static.js.DowngradeComponentAdapter.createComponent (static.js:230)
    at doDowngrade (static.js:528)
    at Object.link (static.js:554)
    at angular.js:1383
    at invokeLinkFn (angular.js:10610)
    at nodeLinkFn (angular.js:9999) "<test-comp>"

Both my AngularJS host component and  are very simple static components. Can't google anything similar. Please help.

A:

The issue apparently was that I've had a more recent version of @angular/upgrade installed (5.2) and it wasn't compatible with other angular packages on my system (5.1).

