src/vs/workbench/services/authentication/browser/authenticationService.ts/AuthenticationService/registerAuthenticationProvider
class AuthenticationService:	registerAuthenticationProvider(id: string, authenticationProvider: MainThreadAuthenticationProvider): void {
		this._authenticationProviders.set(id, authenticationProvider);
		this._onDidRegisterAuthenticationProvider.fire({ id, label: authenticationProvider.label });

		if (this._placeholderMenuItem) {
			this._placeholderMenuItem.dispose();
			this._placeholderMenuItem = undefined;
		}
	}