Well, pick your loading spinner. Either the screen has it for the fetch call, or the whole browser has it for the page-flip (sometimes with you just having a bl

Well, pick your loading spinner. Either the screen has it for the fetch call, or the whole browser has it for the page-flip (sometimes with you just having a blank page while you wait). A long loading spinner is a sign of a server-side problem in speed, not in the client. and old-school MVC page-flipping code can be just as bad in error and validation reporting. Sometimes worse because maybe the form data was lost so you can't fix it. You're talking about design problems that exist regardless of the layer that is involved in showing it. Nothing you've said here is a problem of the UX framework. I use react and we have very extensive error and validation reporting, because we made that a design requirement.