Domain Management: Updating custom name servers doesn't have a loading UI state

[dpasque]

Steps to reproduce the behavior

1. Go to https://wordpress.com/domains/manage for a site with a custom domain
2. Select the custom domain and click the three dots to get the name server settings
3. Click "Change your name servers and DNS"
4. Uncheck the toggle to Use WordPress.com name servers
5. Add two custom name servers (can be anything)
6. Click button to Save Custom Name Servers

What I expected to happen

I expected there to be some kind of loading indication that this saving behavior is going on in the background, but neither the button, nor anything else on this page, goes through any kind of UI state change to indicate a web service is in flight to make the change.

This change often takes at least a couple of seconds to do, so the result is that the user doesn't know their button click has been acknowledged and that the system is working.

You do get a pop-up when the name server change is complete though. There's just nothing in the between time.

Context

Browser / OS version

Chrome 91.0.4472.114 / Mac big sur 11.4

Is this specific to the applied theme? Which one?

Nope

Is there any console output or error text?

Nope

Level of impact (Does it block purchases? Does it affect more than just one site?)

Low level of impact, just may be confusing to users

Reproducibility (Consistent, Intermittent) Leave empty for consistent.

Suggestion Screenshot

I really like the pattern we use on other action buttons across the site where we change the button text slightly and add the is-busy class, and I think we can do that here!

I think this looks kind of nice and communicates what is happening while the save is going on:

[wpericam]

I tested and while there is no indication that the changes is happening, per se, you do pretty quickly get a notification that the change is complete. Will leave open and mark as enhancement for devs to determine if a "processing" indicator of sorts would be helpful.