The cast is not redundant (despite Rider saying so)

src/Website/Controllers/AccountController.cs

@@ -53,7 +53,7 @@ namespace Website.Controllers {
 			await HttpContext.SignInAsync(CookieAuthenticationDefaults.AuthenticationScheme, principal);
 
 			return string.IsNullOrEmpty(returnUrl)
-				? RedirectToAction(nameof(Index))
+				? (IActionResult)RedirectToAction(nameof(Index))
 				: Redirect(returnUrl);
 		}