src/vs/workbench/services/sessionSync/browser/sessionSyncWorkbenchService.ts/SessionSyncWorkbenchService/getAuthenticationProviders
class SessionSyncWorkbenchService:	private async getAuthenticationProviders() {
		if (!this.serverConfiguration) {
			throw new Error('Unable to get configured authentication providers as session sync preference is not configured in product.json.');
		}

		// Get the list of authentication providers configured in product.json
		const authenticationProviders = this.serverConfiguration.authenticationProviders;
		const configuredAuthenticationProviders = Object.keys(authenticationProviders).reduce<IAuthenticationProvider[]>((result, id) => {
			result.push({ id, scopes: authenticationProviders[id].scopes });
			return result;
		}, []);

		// Filter out anything that isn't currently available through the authenticationService
		const availableAuthenticationProviders = this.authenticationService.declaredProviders;

		return configuredAuthenticationProviders.filter(({ id }) => availableAuthenticationProviders.some(provider => provider.id === id));
	}