Check out example codes for "Warning: Flex Layout loaded on the server without FlexLayoutServerModule". It will help you in understanding the concepts better.

Code Example 1

//app.server.module.ts
import {NgModule} from '@angular/core';
import {FlexLayoutServerModule} from '@angular/flex-layout/server';

@NgModule({
  imports: [
    ... other imports here
    FlexLayoutServerModule,
  ]
})
export class AppServerModule {}

//app.module.ts to simulate breakpoints
@NgModule({
  imports: [
	... other imports here
	FlexLayoutModule.withConfig({ssrObserveBreakpoints: ['xs', 'lt-md']})
  ]
})
export class AppModule {}

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