Angular Universal SSR build fails: "this.debug is not a function" during index.html generation

I'm working on an Angular Universal (SSR) project using @angular/cli, and during the SSR build process, I get the following error:

× Index html generation failed.
this.debug is not a function


The browser build completes successfully:

√ Browser application bundle generation complete.

But it fails during the server-side rendering phase.

What I’ve Tried

• Searched my codebase for this.debug() — nothing found.
• Using the default Angular builder: @angular-devkit/build-angular:browser
• I am using SSR with @nguniversal/express-engine
• Here’s a snippet of my server.ts:

const domino = require('domino');
const fs = require('fs');
const path = require('path');
const template = fs.readFileSync(path.join(process.cwd(), 'dist/browser/index.html')).toString();
const win = domino.createWindow(template);
global['window'] = win;
global['document'] = win.document;


There is no direct call to this.debug() in my code. So I suspect a third-party dependency or library might be trying to access window.debug() assuming it’s a function.

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