test(e2e): a page load the machine had no buffer for is tried again

net::ERR_NO_BUFFER_SPACE stopped a release at its first page with nothing else running, and the
unchanged rerun passed. Every page load of the suite now goes through one helper, held by a test.

frontend/src/lib/e2eRetryConnect.test.ts

@@ -1,7 +1,8 @@
 // The e2e suite's request wrapper (e2e/retryConnect.ts): a connect that never came about is tried
 // again, as every TCP stack would; any other failure, or an answer, goes straight to the test.
+import { readdirSync, readFileSync } from "node:fs";
 import { describe, expect, it, vi } from "vitest";
-import { retryConnect } from "../../e2e/retryConnect";
+import { gotoRetrying, retryConnect } from "../../e2e/retryConnect";
 
 const noConnection = () => new Error("apiRequestContext.get: connect ETIMEDOUT 127.0.0.1:8080");
 
@@ -39,3 +40,43 @@ describe("retryConnect", () => {
     vi.useRealTimers();
   });
 });
+
+// The text Playwright gave when this stopped a release's e2e at its first page load (2026-11-04).
+const noBuffer = () => new Error("page.goto: net::ERR_NO_BUFFER_SPACE at http://127.0.0.1:8080/");
+
+describe("gotoRetrying", () => {
+  it("tries a page load the machine had no buffer for again", async () => {
+    vi.useFakeTimers();
+    const goto = vi.fn().mockRejectedValueOnce(noBuffer()).mockResolvedValue("response");
+    const answer = gotoRetrying({ goto }, "/feed");
+    await vi.runAllTimersAsync();
+    await expect(answer).resolves.toBe("response");
+    expect(goto).toHaveBeenCalledTimes(2);
+    expect(goto).toHaveBeenLastCalledWith("/feed");
+    vi.useRealTimers();
+  });
+
+  it("passes any other failure straight on, untried", async () => {
+    const goto = vi.fn().mockRejectedValue(new Error("page.goto: net::ERR_CONNECTION_REFUSED"));
+    await expect(gotoRetrying({ goto }, "/")).rejects.toThrow("ERR_CONNECTION_REFUSED");
+    expect(goto).toHaveBeenCalledTimes(1);
+  });
+
+  it("gives up after its last wait, with the error", async () => {
+    vi.useFakeTimers();
+    const goto = vi.fn().mockRejectedValue(noBuffer());
+    const settled = expect(gotoRetrying({ goto }, "/")).rejects.toThrow("ERR_NO_BUFFER_SPACE");
+    await vi.runAllTimersAsync();
+    await settled;
+    expect(goto).toHaveBeenCalledTimes(6);
+    vi.useRealTimers();
+  });
+
+  it("is the only way the suite loads a page", () => {
+    const dir = new URL("../../e2e/", import.meta.url);
+    const direct = readdirSync(dir)
+      .filter((f) => f.endsWith(".ts") && f !== "retryConnect.ts")
+      .filter((f) => /\.(goto|reload)\(/.test(readFileSync(new URL(f, dir), "utf-8")));
+    expect(direct).toEqual([]);
+  });
+});