diff --git a/src/utils/ci_summary.ts b/src/utils/ci_summary.ts
index 9ae8606..34f9fd7 100644
--- a/src/utils/ci_summary.ts
+++ b/src/utils/ci_summary.ts
@@ -71,7 +71,8 @@ function failuresOf(output: JsonOutput): Failure[] {
 
 /** One line, no table-breaking pipes, bounded length. */
 function cell(text: string, max = 200): string {
-  const flat = text.replace(/\s+/g, ' ').replace(/\|/g, '\\|').trim();
+  // Backslashes too: otherwise an input `\|` becomes `\\|` and the pipe breaks the table.
+  const flat = text.replace(/\s+/g, ' ').replace(/[\\|]/g, '\\$&').trim();
   return flat.length > max ? `${flat.slice(0, max - 1)}…` : flat;
 }
 
diff --git a/tests/utils/ci_summary.test.ts b/tests/utils/ci_summary.test.ts
index e54c464..57635fe 100644
--- a/tests/utils/ci_summary.test.ts
+++ b/tests/utils/ci_summary.test.ts
@@ -84,6 +84,21 @@ describe('renderMarkdown', () => {
     expect(md).not.toContain('search on');
   });
 
+  test('a backslash before a pipe cannot unescape it and break the table', () => {
+    const md = renderMarkdown({
+      ...maestro,
+      runs: [
+        {
+          ...maestro.runs[0],
+          flows: [
+            flow(2, 'checkout', false, { errors: ['path C:\\tmp\\| x'] }),
+          ],
+        },
+      ],
+    });
+    expect(md).toContain('| path C:\\\\tmp\\\\\\| x |');
+  });
+
   test('a passed Espresso run without flows', () => {
     const md = renderMarkdown(espresso);
     expect(md).toContain('### TestingBot Espresso: ✅ passed');