diff --git a/src/symbol/shaping.ts b/src/symbol/shaping.ts
index eb802b9dcdd..772d3923ad0 100644
--- a/src/symbol/shaping.ts
+++ b/src/symbol/shaping.ts
@@ -310,8 +310,12 @@ function shapeText(
             const taggedLine = new TaggedString();
             // Restore zero-width joiners from temporary strip markers.
             taggedLine.text = line[0].replace(/\uF8FF/g, '\u200D');
-            taggedLine.sectionIndex = line[1];
             taggedLine.sections = logicalInput.sections;
+            let elapsedChars = '';
+            for (const char of splitByGraphemeCluster(line[0])) {
+                taggedLine.sectionIndex.push(line[1][elapsedChars.length]);
+                elapsedChars += char;
+            }
             lines.push(taggedLine);
         }
     } else {