test: a five second wait is tight under four workers

e2e/README.md

@@ -411,11 +411,18 @@ Every `waitFor` in this suite takes a timeout, and every one of them is multipli
 
 This is not a way of making a red run green. What a check asserts does not change, and a check whose
 condition never becomes true still fails; it only takes longer to give up. What it buys is the
-difference between the two machines. The whole battery runs one spec at a time and takes about
-thirteen minutes on a workstation and fifteen to twenty-one on the two-core runner, and on
-2026-09-07 three pull requests in a row went red there on waits that no rerun and no local run
-reproduced: eight spec files on one, a single spec on the next, a different single spec on the third.
-A timeout that is generous here is tight there.
+difference between the two machines. On 2026-09-07 three pull requests in a row went red there on
+waits that no rerun and no local run reproduced: eight spec files on one, a single spec on the next,
+a different single spec on the third. A timeout that is generous here is tight there.
+
+**And since N24 it is tight here too.** The battery runs four workers, so four apps share the
+machine and every one of them is slower than it was alone: the paragraph above used to say the
+battery runs one spec at a time, which stopped being true. On 2026-09-12 five batteries in a row
+each dropped one spec, a different one every time, all of them on five second waits. Those thirteen
+waits are fifteen seconds now, raised at their own call sites the way the rule below says. Two were
+left alone on purpose: `asr.spec.js` looks for a dialog that may not be there at all, so its five
+seconds is a cost ceiling rather than a wait, and `video-empty.spec.js` is asking a surface to
+**stay** unmapped rather than to become it.
 
 Two things follow from that. A wait that fails even at twice the timeout is worth reading as a real
 failure rather than as slowness, and a check that needs a longer wait than the suite gives it should

e2e/specs/current-line-bands.spec.js

@@ -618,13 +618,13 @@ async function pickSize(toplevel, percent) {
   const item = `.menubar__item--view-interface-scale-${percent}`;
   await clickElement(toplevel, ".menubar__title--view");
   await waitFor(() => present(item), {
-    timeout: 5000,
+    timeout: 15000,
     message: `the View menu to offer ${percent} per cent`,
   });
   await clickElement(toplevel, item);
   await waitFor(
     async () => (Math.abs((await interfaceScale()) - percent / 100) < 0.001 ? 1 : null),
-    { timeout: 5000, message: `the interface to be drawn at ${percent} per cent` },
+    { timeout: 15000, message: `the interface to be drawn at ${percent} per cent` },
   );
   await browser.pause(250);
 }

e2e/specs/dividers.spec.js

@@ -374,7 +374,7 @@ describe("the shell's three edges", () => {
           return Math.abs(now - before.video) > 100 ? now : null;
         },
         {
-          timeout: 5000,
+          timeout: 15000,
           message: `the video panel to move more than 100px from ${Math.round(before.video)} while the button is still down`,
         },
       );

e2e/specs/grid-columns.spec.js

@@ -424,14 +424,14 @@ async function pickSize(toplevel, percent) {
   const item = `.menubar__item--view-interface-scale-${percent}`;
   await clickElement(toplevel, ".menubar__title--view");
   await waitFor(() => present(item), {
-    timeout: 5000,
+    timeout: 15000,
     message: `the View menu to offer ${percent} per cent`,
   });
   await clickElement(toplevel, item);
   await waitFor(
     async () => (Math.abs((await interfaceScale()) - percent / 100) < 0.001 ? 1 : null),
     {
-      timeout: 5000,
+      timeout: 15000,
       message: `the interface to be drawn at ${percent} per cent`,
     },
   );

e2e/specs/interface-scale.spec.js

@@ -338,13 +338,13 @@ async function pickSize(toplevel, percent) {
   const item = `.menubar__item--view-interface-scale-${percent}`;
   await clickElement(toplevel, ".menubar__title--view");
   await waitFor(() => present(item), {
-    timeout: 5000,
+    timeout: 15000,
     message: `the View menu to offer ${percent} per cent`,
   });
   await clickElement(toplevel, item);
   await waitFor(
     async () => (Math.abs((await interfaceScale()) - percent / 100) < 0.001 ? 1 : null),
-    { timeout: 5000, message: `the interface to be drawn at ${percent} per cent` },
+    { timeout: 15000, message: `the interface to be drawn at ${percent} per cent` },
   );
   // Picking is also what stores the size, and the checks below relaunch the app: a pause here is
   // the same one `dragSash` takes, for the same write.
@@ -737,7 +737,7 @@ describe("the interface size", () => {
           return now.video <= settled.video + SLOP_PX ? now : null;
         },
         {
-          timeout: 5000,
+          timeout: 15000,
           message:
             `the video panel to follow the pointer from ${Math.round(wide.video)} down to ` +
             `${Math.round(settled.video)} while the button is still down`,

e2e/specs/transport-after-open.spec.js

@@ -80,7 +80,7 @@ async function clickTransport(toplevel) {
 /** What the button reads, waited for, with what it actually says when it never gets there. */
 async function expectTransportToRead(wanted) {
   await waitFor(async () => ((await transportLabel()) === wanted ? true : null), {
-    timeout: 5000,
+    timeout: 15000,
     message: `the transport button to read ${JSON.stringify(wanted)}`,
   }).catch(async (error) => {
     const asked = await askedAt();

e2e/specs/waveform-sash.spec.js

@@ -257,7 +257,7 @@ describe("the waveform sash", () => {
     await clickElement(toplevel, ".menubar__title--view");
     await clickElement(toplevel, ".menubar__item--view-waveform-panel");
     await waitFor(async () => !(await present(".waveform")), {
-      timeout: 5000,
+      timeout: 15000,
       message: "the waveform panel to go",
     });
     expect(`the sash went with it: ${await present(SASH)}`).toBe("the sash went with it: false");
@@ -268,7 +268,7 @@ describe("the waveform sash", () => {
     await clickElement(toplevel, ".menubar__title--view");
     await clickElement(toplevel, ".menubar__item--view-waveform-panel");
     await waitFor(() => present(".waveform"), {
-      timeout: 5000,
+      timeout: 15000,
       message: "the waveform panel to come back",
     });
     expect(await heightOf(".currentline")).toBe(withPanel);

e2e/specs/waveform-zoom.spec.js

@@ -106,7 +106,7 @@ async function scaleAfter(press) {
   const before = await scale();
   press();
   await waitFor(async () => (await scale()) !== before, {
-    timeout: 5000,
+    timeout: 15000,
     message: `the scale to move from ${before}`,
   });
   return scale();
@@ -205,7 +205,7 @@ describe("the waveform's zoom is in the registry", () => {
     pressKey("minus");
     pressKey("0");
     await waitFor(async () => (await valueOf(".currentline__text")) !== before, {
-      timeout: 5000,
+      timeout: 15000,
       message: "the three characters to arrive in the text box",
     });
     expect(await valueOf(".currentline__text")).toBe(`${before}+-0`);