🐞 Bug report

Command (mark with an x)

• new
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Is this a regression?

No, breaks after moving to webpack 5

Description

An Angular 11 app with webpack 5 breaks after recompilation (for changes on certain files)

Cannot find module '@angular/core'
at webpackMissingModule ...

🔬 Minimal Reproduction

• git clone https://github.com/difference-engine/ng-webpack5-missing-module.git
• cd ng-webpack5-missing-module
• yarn
• yarn start
• (go to http://localhost:4200/)
• (edit app.module.ts and save)
• refresh browser window, and you should see the error
• (interestingly, doing the same with app.component.html or app.component.ts doesn't break things)

🔥 Exception or Error

🌍 Your Environment

Angular CLI: 11.1.2
Node: 14.15.1
OS: linux x64

Angular: 11.1.1
... animations, common, compiler, compiler-cli, core, forms
... platform-browser, platform-browser-dynamic, router
Ivy Workspace: Yes

Package                         Version
---------------------------------------------------------
@angular-devkit/architect       0.1101.2
@angular-devkit/build-angular   0.1101.2
@angular-devkit/core            11.1.2
@angular-devkit/schematics      11.1.2
@angular/cli                    11.1.2
@schematics/angular             11.1.2
@schematics/update              0.1101.2
rxjs                            6.6.3
typescript                      4.0.5

Anything else relevant?

Originally I had posted this on webpack webpack/webpack#12561
reason for my suspicion was this recent change to rebuildModule in webpack 5 -> webpack/webpack#11433
and the dependency of AngularWebpackPlugin on rebuildModule
But my understanding of both the tools is fairly limited, and webpack folks think this might be a deeper incompatibility with webpack 5