src/components/ErrorBoundary.tsx

@@ -0,0 +1,51 @@
+import { Component, type ErrorInfo, type ReactNode } from "react";
+
+interface Props {
+  children: ReactNode;
+  /** What to show instead of the children. Without it, a full-window notice with a Reload button. */
+  fallback?: (error: Error, reset: () => void) => ReactNode;
+}
+
+interface State {
+  error: Error | null;
+}
+
+/**
+ * React unmounts the whole tree when a component throws and nothing catches it, which leaves a blank window that
+ * looks like a hang. This keeps the failure to the part that threw (or, at the top, shows what happened and a way back).
+ * Plain elements on purpose: the component library may be what threw.
+ */
+export default class ErrorBoundary extends Component<Props, State> {
+  state: State = { error: null };
+
+  static getDerivedStateFromError(error: Error): State {
+    return { error };
+  }
+
+  componentDidCatch(error: Error, info: ErrorInfo) {
+    console.error("Voiced UI error:", error, info.componentStack);
+  }
+
+  reset = () => this.setState({ error: null });
+
+  render() {
+    const { error } = this.state;
+    if (!error) return this.props.children;
+    if (this.props.fallback) return this.props.fallback(error, this.reset);
+    return (
+      <div
+        role="alert"
+        style={{ padding: "2rem", maxWidth: "40rem", margin: "0 auto", color: "var(--cds-text-primary, #161616)", background: "var(--cds-background, #f4f4f4)", minHeight: "100vh" }}
+      >
+        <h1 style={{ fontSize: "1.5rem", marginBottom: "0.75rem" }}>Something went wrong</h1>
+        <p style={{ marginBottom: "1rem" }}>
+          Voiced hit an unexpected error. Your invoices and drafts are saved. Reload to carry on.
+        </p>
+        <pre style={{ whiteSpace: "pre-wrap", fontSize: "0.8125rem", marginBottom: "1.5rem" }}>{error.message}</pre>
+        <button type="button" className="cds--btn cds--btn--primary" onClick={() => window.location.reload()}>
+          Reload Voiced
+        </button>
+      </div>
+    );
+  }
+}

src/components/ExportFeedback.tsx

@@ -1,5 +1,5 @@
 import { useEffect, useState } from "react";
-import { Button, InlineLoading, InlineNotification } from "@carbon/react";
+import { ActionableNotification, Button, InlineLoading, InlineNotification } from "@carbon/react";
 import { api } from "../lib/api";
 import type { InvoiceExport } from "../hooks/useInvoiceExport";
 import FlattenProgressModal from "./FlattenProgressModal";
@@ -37,13 +37,18 @@ export default function ExportFeedback({ exp }: { exp: InvoiceExport }) {
       {busy && !modalOpen ? <InlineLoading description={progress?.phase === "saving" ? "Waiting for the save dialog…" : "Preparing the PDF…"} /> : null}
 
       {error && !flattenFailed ? (
-        <InlineNotification kind="error" lowContrast title="The PDF was not exported" subtitle={error.message} onCloseButtonClick={exp.dismiss}>
+        // Carbon throws if a notification has buttons inside it, and an uncaught throw blanks the whole window.
-          <div className="voiced-notice-actions">
+        // A single action goes through ActionableNotification's own button instead.
-            <Button kind="ghost" size="sm" onClick={exp.retry}>
+        <ActionableNotification
-              Retry
+          inline
-            </Button>
+          kind="error"
-          </div>
+          lowContrast
-        </InlineNotification>
+          title="The PDF was not exported"
+          subtitle={error.message}
+          actionButtonLabel="Retry"
+          onActionButtonClick={exp.retry}
+          onCloseButtonClick={exp.dismiss}
+        />
       ) : null}
 
       {result ? (
@@ -54,7 +59,8 @@ export default function ExportFeedback({ exp }: { exp: InvoiceExport }) {
             title={`Saved to ${result.path}`}
             subtitle={result.identicalToIssued === true ? "The layout is identical to the issued invoice." : undefined}
             onCloseButtonClick={exp.dismiss}
-          >
+          />
+          {/* Beside the notification, not inside it: Carbon throws on interactive children. */}
           <div className="voiced-notice-actions">
             <Button kind="ghost" size="sm" onClick={() => void run(() => api.openFile(result.path))}>
               Open file
@@ -63,7 +69,6 @@ export default function ExportFeedback({ exp }: { exp: InvoiceExport }) {
               Show in folder
             </Button>
           </div>
-          </InlineNotification>
           {result.identicalToIssued === false ? (
             <InlineNotification
               kind="warning"

src/components/notifications.lint.test.ts

@@ -0,0 +1,63 @@
+import { readdirSync, readFileSync, statSync } from "node:fs";
+import path from "node:path";
+import { describe, expect, it } from "vitest";
+
+/**
+ * Carbon's notifications throw "component should have no interactive child nodes" when a button or link sits
+ * inside them, and a throw in an effect unmounts the whole app: the window goes blank (this made every successful
+ * export look like a freeze). There is no DOM test setup here, so this reads the sources instead. Put the
+ * buttons beside the notification, or use ActionableNotification's own action.
+ */
+
+const SRC = path.resolve(process.cwd(), "src");
+const NOTIFICATIONS = ["InlineNotification", "ActionableNotification", "ToastNotification", "Callout"];
+const INTERACTIVE = /<(Button|IconButton|button|a|Link|TextInput|Select|Checkbox|Toggle|OverflowMenu|ComboBox|Dropdown)\b/;
+
+function sourceFiles(dir: string): string[] {
+  return readdirSync(dir).flatMap((name) => {
+    const full = path.join(dir, name);
+    if (statSync(full).isDirectory()) return name === "pdf" ? [] : sourceFiles(full);
+    return /\.tsx$/.test(name) && !/\.test\.tsx$/.test(name) ? [full] : [];
+  });
+}
+
+/** Bodies of the notifications that have children, with the line they start on. */
+function notificationBodies(source: string): Array<{ tag: string; line: number; body: string }> {
+  const out: Array<{ tag: string; line: number; body: string }> = [];
+  for (const tag of NOTIFICATIONS) {
+    const open = new RegExp(`<${tag}\\b`, "g");
+    for (let m = open.exec(source); m; m = open.exec(source)) {
+      let i = m.index + m[0].length;
+      let braces = 0;
+      for (; i < source.length; i++) {
+        const c = source[i];
+        if (c === "{") braces++;
+        else if (c === "}") braces--;
+        else if (c === ">" && braces === 0) break;
+      }
+      if (source[i - 1] === "/") continue; // self-closing: no children
+      const end = source.indexOf(`</${tag}>`, i);
+      out.push({ tag, line: source.slice(0, m.index).split("\n").length, body: source.slice(i + 1, end < 0 ? undefined : end) });
+    }
+  }
+  return out;
+}
+
+describe("Carbon notifications", () => {
+  it("never wrap an interactive element", () => {
+    const offenders: string[] = [];
+    for (const file of sourceFiles(SRC)) {
+      for (const { tag, line, body } of notificationBodies(readFileSync(file, "utf8"))) {
+        if (INTERACTIVE.test(body)) offenders.push(`${path.relative(SRC, file)}:${line} <${tag}>`);
+      }
+    }
+    expect(offenders).toEqual([]);
+  });
+
+  it("the scan finds an offender when there is one", () => {
+    const bad = `<InlineNotification kind="success" title="x">\n  <Button>Open</Button>\n</InlineNotification>`;
+    const fine = `<InlineNotification kind="success" title="x" />\n<Button>Open</Button>`;
+    expect(notificationBodies(bad).some((n) => INTERACTIVE.test(n.body))).toBe(true);
+    expect(notificationBodies(fine)).toEqual([]);
+  });
+});

src/lib/selfTestE2e.ts

@@ -125,6 +125,8 @@ export async function runE2eSteps(log: StepLog, reportPath: string): Promise<voi
     return { ok: r?.path === searchablePath, detail: `wrote ${r?.path}` };
   });
 
+  await log.run("e2e: export notices render without crashing the window", async () => (await import("./selfTestUi")).checkExportFeedbackRenders());
+
   await log.run("e2e: export flattened original", async () => {
     const r = await exportWith("flattened", "original", flattenedPath);
     return { ok: r?.path === flattenedPath, detail: `wrote ${r?.path}` };
@@ -158,6 +160,17 @@ export async function runE2eSteps(log: StepLog, reportPath: string): Promise<voi
     };
   });
 
+  await log.run("e2e: a new invoice can be issued and exported after the first", async () => {
+    const first = inv.number;
+    const outcome = await issueAndArchive({ ...input, notes: "Self-test invoice 2" }, prefs, deps);
+    const next = `${outDir}/e2e-second.pdf`;
+    const r = await exportInvoice({ invoice: outcome.invoice, mode: "searchable", source: "original" }, { ...deps, save: async () => next });
+    return {
+      ok: outcome.archived && outcome.invoice.number !== first && r?.path === next,
+      detail: `${first}, then ${outcome.invoice.number} (archived=${outcome.archived}), exported ${r?.path}`,
+    };
+  });
+
   await log.run("e2e: archiving different bytes is refused", async () => {
     const other = new TextEncoder().encode("%PDF-1.4\n% a different file\n");
     const before = await api.readArchive(inv.id);

src/lib/selfTestUi.tsx

@@ -0,0 +1,59 @@
+import { createRoot } from "react-dom/client";
+import { Theme } from "@carbon/react";
+import ExportFeedback from "../components/ExportFeedback";
+import type { InvoiceExport } from "../hooks/useInvoiceExport";
+import type { Invoice } from "./types";
+
+/**
+ * Part of the real-webview self-test: mounts the export notices the way the app does and fails if React reports an
+ * uncaught error. Carbon throws when a notification has a button inside it, and that took the whole window
+ * down after every successful export; nothing that runs without a real DOM can see it.
+ */
+
+const noop = () => {};
+const idle: InvoiceExport = {
+  busy: false,
+  progress: null,
+  request: null,
+  error: null,
+  result: null,
+  start: async () => null,
+  cancel: noop,
+  retry: noop,
+  exportSearchableInstead: noop,
+  dismiss: noop,
+};
+
+const CASES: Array<{ name: string; expect: string; exp: InvoiceExport }> = [
+  {
+    name: "saved",
+    expect: "Saved to",
+    exp: { ...idle, result: { path: "/tmp/voiced-selftest.pdf", mode: "searchable", invoice: {} as Invoice, identicalToIssued: false, archiveError: "not archived" } },
+  },
+  { name: "failed", expect: "was not exported", exp: { ...idle, error: { message: "disk full", flatten: false } } },
+];
+
+export async function checkExportFeedbackRenders(): Promise<{ ok: boolean; detail: string }> {
+  const problems: string[] = [];
+  for (const c of CASES) {
+    const host = document.createElement("div");
+    document.body.appendChild(host);
+    const errors: string[] = [];
+    const root = createRoot(host, {
+      onUncaughtError: (e) => errors.push(e instanceof Error ? e.message : String(e)),
+      onRecoverableError: (e) => errors.push(e instanceof Error ? e.message : String(e)),
+    });
+    root.render(
+      <Theme theme="g10">
+        <ExportFeedback exp={c.exp} />
+      </Theme>,
+    );
+    // Effects (where Carbon checks its children) run after the first paint.
+    await new Promise((r) => setTimeout(r, 400));
+    if (errors.length > 0) problems.push(`${c.name}: ${errors.join("; ").slice(0, 300)}`);
+    else if (!(host.textContent ?? "").includes(c.expect)) problems.push(`${c.name}: the notice did not render`);
+    root.unmount();
+    host.remove();
+  }
+  return { ok: problems.length === 0, detail: problems.join(" | ") || "the saved and failed notices render without throwing" };
+}

src/main.tsx

@@ -1,12 +1,15 @@
 import React from "react";
 import { createRoot } from "react-dom/client";
 import App from "./App";
+import ErrorBoundary from "./components/ErrorBoundary";
 import "./styles/carbon.scss";
 import { maybeRunSelfTest } from "./selftestBoot";
 
 createRoot(document.getElementById("root") as HTMLElement).render(
   <React.StrictMode>
+    <ErrorBoundary>
       <App />
+    </ErrorBoundary>
   </React.StrictMode>,
 );
 

src/views/InvoiceDetail.tsx

@@ -44,6 +44,7 @@ import {
   syncTag,
 } from "../lib/erpnextUi";
 import { useReturnFocus } from "../hooks/useReturnFocus";
+import ErrorBoundary from "../components/ErrorBoundary";
 import ExportFeedback from "../components/ExportFeedback";
 import PdfPreview from "../components/PdfPreview";
 import RecordPaymentModal from "../components/RecordPaymentModal";
@@ -385,7 +386,9 @@ export default function InvoiceDetail({ invoiceId, settings, onBack, onDuplicate
         </OverflowMenu>
       </div>
 
+      <ErrorBoundary fallback={(e) => <p className="voiced-muted">The export result could not be shown ({e.message}). The PDF was still saved.</p>}>
                 <ExportFeedback exp={exp} />
+              </ErrorBoundary>
 
       <div className="voiced-detail__grid">
         <div className="voiced-detail__main voiced-stack">

src/views/InvoiceHistory.tsx

@@ -49,6 +49,7 @@ import { openInErpnext } from "../lib/erpnextActions";
 import type { ErpnextConfig, ErpnextSyncStatus } from "../lib/erpnext";
 import { canOpenInErpnext, indexSyncStatuses, isConfigured, pushDisabledReason, sendableSelection, syncTag } from "../lib/erpnextUi";
 import SendToErpnextModal, { type SendTarget } from "../components/SendToErpnextModal";
+import ErrorBoundary from "../components/ErrorBoundary";
 import ExportFeedback from "../components/ExportFeedback";
 import { useToast } from "../components/ToastProvider";
 import type { InvoiceSummary, Settings } from "../lib/types";
@@ -226,7 +227,9 @@ export default function InvoiceHistory({ settings, active, onOpen, onOpenSetting
       <h1 className="voiced-page__title">Invoices</h1>
       <p className="voiced-page__subtitle">Every invoice you have issued. Open one to see its PDF, record payments or export it.</p>
 
+      <ErrorBoundary fallback={(e) => <p className="voiced-muted">The export result could not be shown ({e.message}). The PDF was still saved.</p>}>
         <ExportFeedback exp={exp} />
+      </ErrorBoundary>
 
       {loading ? (
         <InlineLoading description="Loading invoices" />

src/views/NewInvoice.tsx

@@ -61,6 +61,7 @@ import { useInvoicePdf } from "../hooks/useInvoicePdf";
 import { useInvoiceExport } from "../hooks/useInvoiceExport";
 import { autoPushIssued } from "../lib/erpnextUi";
 import ExportButton, { ExportModePicker } from "../components/ExportButton";
+import ErrorBoundary from "../components/ErrorBoundary";
 import ExportFeedback from "../components/ExportFeedback";
 import { createExportDeps } from "../lib/exportDeps";
 import { issueAndArchive, renderAndArchive } from "../lib/exportFlow";
@@ -784,7 +785,9 @@ export default function NewInvoice({ settings, onSettingsChange, active, onActiv
                   onActionButtonClick={() => void retryArchive()}
                 />
               ) : null}
+              <ErrorBoundary fallback={(e) => <p className="voiced-muted">The export result could not be shown ({e.message}). The PDF was still saved.</p>}>
                 <ExportFeedback exp={exp} />
+              </ErrorBoundary>
               <div className="voiced-header-action" style={{ flexWrap: "wrap", marginTop: "0.5rem" }}>
                 <ExportButton onExport={(mode) => void exp.start(exportable, mode, "original")} disabled={busy} />
                 <Button kind="tertiary" renderIcon={Copy} onClick={duplicateAsNew} disabled={busy}>