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I have an Angular 6 project I would like to upgrade to Angular 10, but I have read it’s best to do it one major version at a time, so I am trying to get it to 7.3 for now. I have followed all the steps on update.angular.io, but I am beginning to think it’s not a very complete guide. This question will be broken up into several sub-questions:

1. After upgrading Angular Core and CLI (ng update @angular/cli@7 @angular/core@7), I tried to run “ng serve”, but then get these compile errors:

...

I'm trying to get my build much smaller to get my load time faster, but when I run

ng build --prod --aot --vendor-chunk --common-chunk --build-optimizer and then run a lighthouse report from google dev tools

I get

what's odd is that it seems to have worked if I go into the dist folder to look at file sizes, which seem smaller that the lighthouse report.

So far to reduce the size by doing the following:

• Removed old/unused package.json entries
• changed all material imports to specific path like for paginator I'm importing now as import { MatPaginator } from "@angular/material/paginator"; instead of import { MatPaginator } from "@angular/material/"; per the advice from other posts.
• replaced moment with moment.min.js so that locales don't get added
• added brotli for text compression.

Also I want to mention because I don't know if it's relevant, but I don't have a webpack.config.js file only a custom-webpack.config.js for brotli. The only thing I edited in angular.json to get webpack working was this for brotli