getExtUri error when using monaco-languageclient with Angular 20 (Angular build system)

[vishnuvarthan-balasubramaniam]

We are currently trying to integrate monaco-editor with monaco-languageclient to enable LSP (Language Server Protocol) support in an Angular 20 application using the standard Angular build system (Angular CLI / esbuild).

We have reviewed the Angular example provided in the repository, which is implemented using the Vite build system. That example works as expected. However, when attempting to achieve the same setup using Angular’s default build system, we consistently encounter a runtime error related to getExtUri, regardless of changes made to imports, modules, or package versions.

Environment

Framework: Angular 20
Build system: Angular CLI (default Angular build / esbuild)
Packages: monaco-languageclient v10.6.0

Could you please clarify one of the following:

1. Is the Angular CLI / Angular build system officially supported for monaco-languageclient?
2. Are there known limitations or required configurations when using Angular instead of Vite?
3. Is there an example repository demonstrating monaco-editor + monaco-languageclient using:
   • 4.Angular CLI
   • Angular’s default build system (esbuild)
4. If Angular CLI is not supported at the moment, could this be documented explicitly?

We can provide a minimal reproduction repository if required.
Thank you in advance for your time and support.

[kaisalmen]

See #1015