Performance: Parallelize independent boot API requests (server status/config + public extensions)

src/Umbraco.Web.UI.Client/src/apps/app/app.element.ts

@@ -258,8 +258,11 @@ export class UmbAppElement extends UmbLitElement {
 		// Register Core extensions (this is specifically done here because we need these extensions to be registered before the application is initialized)
 		onInit(this, umbExtensionsRegistry);
 
-		// Register public extensions (login extensions)
-		await new UmbServerExtensionRegistrator(this, umbExtensionsRegistry).registerPublicExtensions();
+		// Register public extensions (login extensions) in parallel with the auth flow below.
+		const registerPublicExtensions = new UmbServerExtensionRegistrator(
+			this,
+			umbExtensionsRegistry,
+		).registerPublicExtensions();
 		new UmbAppEntryPointExtensionInitializer(this, umbExtensionsRegistry);
 
 		// Try to initialise the auth flow and get the runtime status
@@ -276,6 +279,9 @@ export class UmbAppElement extends UmbLitElement {
 				await this.#setAuthStatus();
 			}
 
+			// The login screen needs the public extensions before routing.
+			await registerPublicExtensions;
+
 			// Initialise the router
 			this.#redirect();
 		} catch (error) {

src/Umbraco.Web.UI.Client/src/packages/core/server/server-connection.ts

@@ -45,8 +45,15 @@ export class UmbServerConnection extends UmbControllerBase {
 	 * @memberof UmbServerConnection
 	 */
 	async connect() {
-		await this.#setStatus();
-		await this.#setServerConfiguration();
+		// Independent reads, but both are required for the backoffice to function.
+		const results = await Promise.allSettled([this.#setStatus(), this.#setServerConfiguration()]);
+		const errors = results
+			.filter((result): result is PromiseRejectedResult => result.status === 'rejected')
+			.map((result) => result.reason);
+		if (errors.length) {
+			throw errors.length === 1 ? errors[0] : new AggregateError(errors, 'Failed to connect to the Umbraco server');
+		}
+		this.#isConnected.setValue(true);
 		return this;
 	}
 
@@ -86,7 +93,6 @@ export class UmbServerConnection extends UmbControllerBase {
 			throw error;
 		}
 
-		this.#isConnected.setValue(true);
 		this.#status = data?.serverStatus ?? RuntimeLevelModel.UNKNOWN;
 	}