From 1328098c452819921c48b01b1828d6f3371e1333 Mon Sep 17 00:00:00 2001
From: Arnaud Robin <arnaud.robin@beta.gouv.fr>
Date: Tue, 4 Aug 2026 15:47:42 +0200
Subject: [PATCH] =?UTF-8?q?=F0=9F=90=9B(frontend)=20keep=20Unicode=20initi?=
 =?UTF-8?q?als=20intact=20in=20avatar?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Some characters span multiple UTF-16 code units. Taking a naive first
index for avatar initials can split them and show a broken glyph when
the camera is off.

Optically fix initials centering with a more complex approach.
---
 CHANGELOG.md                           |  1 +
 src/frontend/src/components/Avatar.tsx | 66 +++++++++++++++++++++++---
 2 files changed, 60 insertions(+), 7 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 79bc89eb..7ac4ffb1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -47,6 +47,7 @@ and this project adheres to
 - 🐛(backend) serialize lazy title in summary payload
 - 💄(frontend) show pointer cursor on interactive switches
 - 🐛(frontend) fix icon centering in the Switch primitive
+- 🐛(frontend) keep Unicode initials intact in avatar
 
 ## [1.24.0] - 2026-07-21
 
diff --git a/src/frontend/src/components/Avatar.tsx b/src/frontend/src/components/Avatar.tsx
index 4a4feb60..36bf7257 100644
--- a/src/frontend/src/components/Avatar.tsx
+++ b/src/frontend/src/components/Avatar.tsx
@@ -1,5 +1,5 @@
 import { css, cva, RecipeVariantProps } from '@/styled-system/css'
-import React from 'react'
+import React, { useLayoutEffect, useMemo } from 'react'
 
 const avatar = cva({
   base: {
@@ -28,13 +28,34 @@ const avatar = cva({
   },
 })
 
+// Instantiating a segmenter is expensive; create it once and reuse it.
+const graphemeSegmenter =
+  typeof Intl !== 'undefined' && 'Segmenter' in Intl
+    ? new Intl.Segmenter(undefined, { granularity: 'grapheme' })
+    : undefined
+
+/**
+ * Returns the first user-perceived character. Some Unicode characters span
+ * multiple UTF-16 code units, so a naive index into the string can split them
+ * and yield a broken glyph.
+ */
+const getFirstGrapheme = (value: string): string => {
+  if (!value) return ''
+  if (graphemeSegmenter) {
+    const [first] = graphemeSegmenter.segment(value)
+    return first?.segment ?? ''
+  }
+  // Fallback: keeps single code points intact (including surrogate pairs).
+  return Array.from(value)[0] ?? ''
+}
+
 const getInitials = (name?: string): string => {
   if (!name) return ''
   const words = name.trim().split(/\s+/).filter(Boolean)
   if (words.length === 0) return ''
-  const first = words[0].charAt(0)
-  const second = words.length > 1 ? words[1].charAt(0) : ''
-  return (first + second).toUpperCase()
+  const first = getFirstGrapheme(words[0])
+  const second = words.length > 1 ? getFirstGrapheme(words[1]) : ''
+  return (first + second).toLocaleUpperCase()
 }
 
 export type AvatarProps = React.HTMLAttributes<HTMLDivElement> & {
@@ -44,7 +65,37 @@ export type AvatarProps = React.HTMLAttributes<HTMLDivElement> & {
 
 export const Avatar = React.memo(
   ({ name, bgColor, context, notification, style, ...props }: AvatarProps) => {
-    const initials = getInitials(name)
+    const initials = useMemo(() => getInitials(name), [name])
+    const textRef = React.useRef<SVGTextElement>(null)
+    const [offsetY, setOffsetY] = React.useState(0)
+
+    // Optically center the initials: measure the ink bounding box of the
+    // rendered glyphs and shift them so the box's center sits at the middle
+    // of the viewBox. Works for any font, weight or glyph shape, unlike a
+    // hand-tuned dy offset. getBBox() is in local (pre-transform)
+    // coordinates, so applying the translation never changes the measure.
+    useLayoutEffect(() => {
+      const text = textRef.current
+      if (!text) return
+
+      const center = () => {
+        const box = text.getBBox()
+        // A hidden element measures as an empty box; keep the default then.
+        if (box.height === 0) return
+        setOffsetY(50 - (box.y + box.height / 2))
+      }
+
+      center()
+      // Glyph metrics can change once webfonts finish loading.
+      let cancelled = false
+      document.fonts?.ready.then(() => {
+        if (!cancelled) center()
+      })
+      return () => {
+        cancelled = true
+      }
+    }, [initials])
+
     return (
       <div
         style={{ backgroundColor: bgColor, ...style }}
@@ -57,16 +108,17 @@ export const Avatar = React.memo(
           className={css({ width: '100%', height: '100%', display: 'block' })}
         >
           <text
+            ref={textRef}
             x="50"
             y="50"
-            dy="-0.08em"
+            transform={`translate(0 ${offsetY})`}
             textAnchor="middle"
             dominantBaseline="central"
             fontSize="52"
             fontWeight="500"
             fill="currentColor"
           >
-            {initials.toUpperCase()}
+            {initials}
           </text>
         </svg>
       </div>