diff --git a/crates/math-core/src/commands.rs b/crates/math-core/src/commands.rs
index 531f34fd..6f56cfe0 100644
--- a/crates/math-core/src/commands.rs
+++ b/crates/math-core/src/commands.rs
@@ -28,7 +28,7 @@ static COMMANDS: phf::Map<&'static str, Token> = phf::phf_map! {
     "." => TextMode(TextToken::Accent(symbol::COMBINING_DOT_ABOVE.as_op().as_char())),
     ":" => MathOrTextMode(&Space(LatexUnit::Mu.length_with_unit(4.0)), '\u{205F}'),
     ";" => MathOrTextMode(&Space(LatexUnit::Mu.length_with_unit(5.0)), '\u{2004}'),
-    "=" => TextMode(TextToken::Accent(symbol::COMBINING_OVERLINE)),
+    "=" => TextMode(TextToken::Accent(symbol::COMBINING_OVERLINE.as_op().as_char())),
     ">" => MathOrTextMode(&Space(LatexUnit::Mu.length_with_unit(4.0)), '\u{205F}'),
     "AA" => TextMode(TextToken::Letter('Å')),
     "AE" => TextMode(TextToken::Letter('Æ')),
@@ -142,7 +142,7 @@ static COMMANDS: phf::Map<&'static str, Token> = phf::phf_map! {
     "backsimeq" => Relation(symbol::REVERSED_TILDE_EQUALS),
     "backslash" => Ord(symbol::REVERSE_SOLIDUS),
     "backtrprime" => Ord(symbol::REVERSED_TRIPLE_PRIME),
-    "bar" => Accent(symbol::LOW_LINE, true, OpAttrs::STRETCHY_FALSE),
+    "bar" => Accent(symbol::COMBINING_MACRON, true, OpAttrs::empty()),
     "barwedge" => BinaryOp(symbol::NAND),
     "bcancel" => Enclose(Notation::DOWN_DIAGONAL),
     "because" => Relation(symbol::BECAUSE),
diff --git a/crates/math-core/tests/snapshots/wiki_test__wiki007.snap b/crates/math-core/tests/snapshots/wiki_test__wiki007.snap
index cdcdfdc4..8e73dfe6 100644
--- a/crates/math-core/tests/snapshots/wiki_test__wiki007.snap
+++ b/crates/math-core/tests/snapshots/wiki_test__wiki007.snap
@@ -20,6 +20,6 @@ expression: "\\check{a}, \\breve{a}, \\tilde{a}, \\bar{a}"
     <mo>,</mo>
     <mover accent="true">
         <mi>a</mi>
-        <mo stretchy="false">_</mo>
+        <mo>̄</mo>
     </mover>
 </math>
diff --git a/crates/math-core/tests/snapshots/wiki_test__wiki112.snap b/crates/math-core/tests/snapshots/wiki_test__wiki112.snap
index 76cccae9..8b02b586 100644
--- a/crates/math-core/tests/snapshots/wiki_test__wiki112.snap
+++ b/crates/math-core/tests/snapshots/wiki_test__wiki112.snap
@@ -10,7 +10,7 @@ expression: "\\hat a \\ \\bar b \\ \\vec c \\\\ \\overrightarrow{a b} \\ \\overl
     <mtext> </mtext>
     <mover accent="true">
         <mi>b</mi>
-        <mo stretchy="false">_</mo>
+        <mo>̄</mo>
     </mover>
     <mtext> </mtext>
     <mover accent="true">
diff --git a/crates/math-core/tests/snapshots/wiki_test__wiki212.snap b/crates/math-core/tests/snapshots/wiki_test__wiki212.snap
index 79d97ebd..3505dbc9 100644
--- a/crates/math-core/tests/snapshots/wiki_test__wiki212.snap
+++ b/crates/math-core/tests/snapshots/wiki_test__wiki212.snap
@@ -6,7 +6,7 @@ expression: "|\\bar{z}| = |z|, |(\\bar{z})^n| = |z|^n, \\arg(z^n) = n \\arg(z)"
     <mo stretchy="false" lspace="0" rspace="0">|</mo>
     <mover accent="true">
         <mi>z</mi>
-        <mo stretchy="false">_</mo>
+        <mo>̄</mo>
     </mover>
     <mo stretchy="false" lspace="0" rspace="0">|</mo>
     <mo>=</mo>
@@ -18,7 +18,7 @@ expression: "|\\bar{z}| = |z|, |(\\bar{z})^n| = |z|^n, \\arg(z^n) = n \\arg(z)"
     <mo stretchy="false">(</mo>
     <mover accent="true">
         <mi>z</mi>
-        <mo stretchy="false">_</mo>
+        <mo>̄</mo>
     </mover>
     <msup>
         <mo stretchy="false">)</mo>
diff --git a/crates/mathml-renderer/src/symbol.rs b/crates/mathml-renderer/src/symbol.rs
index 5518f9d5..01229740 100644
--- a/crates/mathml-renderer/src/symbol.rs
+++ b/crates/mathml-renderer/src/symbol.rs
@@ -363,8 +363,8 @@ pub const COMBINING_GRAVE_ACCENT: Rel = Rel::new('\u{300}', RelCategory::Default
 pub const COMBINING_ACUTE_ACCENT: Rel = Rel::new('\u{301}', RelCategory::Default);
 pub const COMBINING_CIRCUMFLEX_ACCENT: Rel = Rel::new('\u{302}', RelCategory::Default);
 pub const COMBINING_TILDE: Rel = Rel::new('\u{303}', RelCategory::Default);
-// pub const COMBINING_MACRON: char = '\u{304}';
-pub const COMBINING_OVERLINE: char = '\u{305}';
+pub const COMBINING_MACRON: Rel = Rel::new('\u{304}', RelCategory::Default);
+pub const COMBINING_OVERLINE: Rel = Rel::new('\u{305}', RelCategory::Default);
 pub const COMBINING_BREVE: Rel = Rel::new('\u{306}', RelCategory::Default);
 pub const COMBINING_DOT_ABOVE: Rel = Rel::new('\u{307}', RelCategory::Default);
 pub const COMBINING_DIAERESIS: Rel = Rel::new('\u{308}', RelCategory::Default);
diff --git a/playground/LibertinusMath-Regular.woff2 b/playground/LibertinusMath-Regular.woff2
index 14e3bb65..688869c9 100644
Binary files a/playground/LibertinusMath-Regular.woff2 and b/playground/LibertinusMath-Regular.woff2 differ
diff --git a/playground/NewCMMath-Book-prime-roundhand-vec.woff2 b/playground/NewCMMath-Book-prime-roundhand-vec.woff2
index 1aecf95d..5ce6ae41 100644
Binary files a/playground/NewCMMath-Book-prime-roundhand-vec.woff2 and b/playground/NewCMMath-Book-prime-roundhand-vec.woff2 differ
diff --git a/playground/NotoSansMath-Regular-centered-diacritics-primes.woff2 b/playground/NotoSansMath-Regular-centered-diacritics-primes.woff2
index 02bb412a..de3b3401 100644
Binary files a/playground/NotoSansMath-Regular-centered-diacritics-primes.woff2 and b/playground/NotoSansMath-Regular-centered-diacritics-primes.woff2 differ
diff --git a/playground/experiments.html b/playground/experiments.html
index 2b464500..d32c609d 100644
--- a/playground/experiments.html
+++ b/playground/experiments.html
@@ -158,18 +158,18 @@ <h1>Experiments</h1>
                                     </math>
                             <tr>
                                 <td>
-                                    Macron, stretchy=false
+                                    COMBINING MACRON, stretchy=false
                                 <td>
                                     <math display="block">
                                         <mover accent="true">
                                             <mi>x</mi>
-                                            <mo stretchy="false">¯</mo>
+                                            <mo stretchy="false">&#x304;</mo>
                                         </mover>
                                     </math>
                             </tr>
                             <tr>
                                 <td>
-                                    Macron, stretchy=true
+                                    COMBINING MACRON
                                 <td>
                                     <math display="block">
                                         <mover accent="true">
@@ -178,7 +178,7 @@ <h1>Experiments</h1>
                                                 <mi>y</mi>
                                                 <mi>z</mi>
                                             </mrow>
-                                            <mo stretchy="true">¯</mo>
+                                            <mo>&#x304;</mo>
                                         </mover>
                                     </math>
                             </tr>
diff --git a/playground/test.html b/playground/test.html
index 2399ee19..e0e398f7 100644
--- a/playground/test.html
+++ b/playground/test.html
@@ -32,7 +32,7 @@
 <math display="block">
     <mover accent="true">
         <mi>x</mi>
-        <mo stretchy="false">_</mo>
+        <mo>̄</mo>
     </mover>
     <mo>,</mo>
     <mover accent="true">