When the following message is displayed by Visual Studio Code for an angular project, it’s time to switch from TSMint to ESLint, as TSLint has been deprecated for a while now.

Not using the local TSLint version found for 'c:/Users/nicol/Documents/GitHub/Bartleby/frontend/src/app/create-dossier/create-dossier.component.ts'
 To enable code execution from the current workspace you must enable workspace library execution.

This documentation from Microsoft describes the process : https://code.visualstudio.com/api/advanced-topics/tslint-eslint-migration

To display a loader while waiting for an AJAX call to be processed, use a template, and an *ngIf / else condition on a container.

Example, with ng zorro :

<ng-container *ngIf="!saving else loading">
Will be displayed once the "saving" variable is false.
</ng-container>

<ng-template #loading>
  <div nz-row nzJustify="center">
    <nz-spin nzSimple></nz-spin> Displayed as long as the "saving" variable is true ...
  </div>
</ng-template>