Table of Contents Documentation

Moving between the plugin's screens does not reload the page, and neither does saving. The screen is fetched and swapped in, the address bar keeps up, and the back button works exactly as it did.

It is an enhancement, not a dependency. If a fetch fails, or the browser has JavaScript switched off, links navigate and forms submit the way they always have — the server side is unchanged, and the same handlers, redirects and nonce checks run either way.

Two things make it feel immediate rather than merely quicker:

• The next screen is usually already fetched. Moving a pointer to a menu item takes a couple of hundred milliseconds, and that time is spent fetching the screen it points at. By the time the click lands there is often nothing left to wait for.
• A screen you have already seen is reused for half a minute. Saving anything throws all of that away rather than guessing which screens a save might have changed.

Saving says so in a small message in the top-right corner, which clears itself after about three seconds. Hover it and it waits; press the × and it goes.

Why a tab changes instantly

A WordPress admin request spends about a second inside WordPress before a plugin's own code runs. Fetching a screen when your pointer reaches its tab only recovers the two or three hundred milliseconds the pointer was travelling.

So the plugin does not wait for the pointer. Once the screen you asked for is on the glass and the browser reports itself idle, the other screens are fetched in the background — one at a time, never in parallel, so a small host sees no more load than somebody clicking through the tabs slowly would have caused. The fetching stops the moment you navigate, because what you asked for matters more than what was guessed, and it does not happen at all on a metered connection.

A fetched screen is reused for five minutes. Saving anything discards all of them rather than guessing which screens a save might have changed, and a screen older than twenty seconds is still shown at once and quietly refreshed behind it, so what you see is never more than one navigation out of date.