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diff --git a/docs/showcase/newsletter.docx b/docs/showcase/newsletter.docx
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diff --git a/docs/showcase/thesis-review.docx b/docs/showcase/thesis-review.docx
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diff --git a/docs/showcase/thesis-review.odt b/docs/showcase/thesis-review.odt
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diff --git a/docs/showcase/thesis.docx b/docs/showcase/thesis.docx
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diff --git a/docs/showcase/thesis.odt b/docs/showcase/thesis.odt
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diff --git a/src/lib/math/mathml.ts b/src/lib/math/mathml.ts
index 440dc6d..bef75ae 100644
--- a/src/lib/math/mathml.ts
+++ b/src/lib/math/mathml.ts
@@ -13,6 +13,8 @@ const esc = (s: string) =>
 
 const TAG_BY_KIND: Record<TxtKind, string> = { i: 'mi', n: 'mn', o: 'mo', f: 'mi' };
 
+const BRACKETS = /^[([{|‖⟨⌊⌈)\]}⟩⌋⌉]$/;
+
 // A row that MathML needs as a single element (mfrac, msup, … each take exactly one
 // child per slot), so a multi-node row is wrapped in <mrow>.
 function slot(n: MathNode): string {
@@ -27,7 +29,9 @@ export function astToMathml(n: MathNode): string {
       if (n.kind === 'f') return `<mi mathvariant="normal">${esc(n.s)}</mi>`;
       // Multi-letter identifiers stay upright in MathML unless split, and a number
       // like 3.14 is one token — so emit the run whole and let the class pick the tag.
-      return `<${TAG_BY_KIND[n.kind]}>${esc(n.s)}</${TAG_BY_KIND[n.kind]}>`;
+      // A bracket typed without \left stays glyph-height; only a fence stretches.
+      const attr = n.kind === 'o' && BRACKETS.test(n.s) ? ' stretchy="false"' : '';
+      return `<${TAG_BY_KIND[n.kind]}${attr}>${esc(n.s)}</${TAG_BY_KIND[n.kind]}>`;
     }
     case 'frac': return `<mfrac>${slot(n.num)}${slot(n.den)}</mfrac>`;
     case 'script': {
diff --git a/tests/unit/math.test.ts b/tests/unit/math.test.ts
index 4b70122..4491cf3 100644
--- a/tests/unit/math.test.ts
+++ b/tests/unit/math.test.ts
@@ -54,6 +54,8 @@ describe('MathML', () => {
     expect(astToMathml(parseLatex('\\int_{0}^{1} x'))).toContain('<msubsup>');
     // Brackets must be stretchy or they stay glyph-height next to a fraction.
     expect(astToMathml(parseLatex('\\left(x\\right)'))).toContain('<mo stretchy="true">(</mo>');
+    // A plain bracket must not: the dictionary would stretch it to the row's tallest.
+    expect(astToMathml(parseLatex('C(b) = \\frac{1}{2}'))).toContain('<mo stretchy="false">(</mo>');
   });
 
   it('round-trips through the document element', () => {