diff --git a/src/renderer/src/components/TaskPage.tsx b/src/renderer/src/components/TaskPage.tsx
index cf6e884b7b0..b0265713971 100644
--- a/src/renderer/src/components/TaskPage.tsx
+++ b/src/renderer/src/components/TaskPage.tsx
@@ -1438,25 +1438,14 @@ function ReviewChipAvatar({
 }
 
 function GitHubAssigneeAvatar({ assignee }: { assignee: GitHubAssignableUser }): React.JSX.Element {
-  if (assignee.avatarUrl) {
-    return (
-      <img
-        src={assignee.avatarUrl}
-        alt={assignee.login}
-        loading="lazy"
-        decoding="async"
-        title={assignee.name ? `${assignee.name} (${assignee.login})` : assignee.login}
-        className="size-5 rounded-full border border-border/40 bg-muted object-cover"
-      />
-    )
-  }
   return (
-    <span
-      title={assignee.login}
-      className="inline-flex size-5 items-center justify-center rounded-full border border-border/40 bg-muted text-[10px] font-medium text-muted-foreground"
-    >
-      {assignee.login.slice(0, 1).toUpperCase()}
-    </span>
+    <GitHubUserAvatar
+      login={assignee.login}
+      name={assignee.name}
+      avatarUrl={assignee.avatarUrl}
+      title={assignee.name ? `${assignee.name} (${assignee.login})` : assignee.login}
+      className="size-5"
+    />
   )
 }
 
@@ -1896,13 +1885,12 @@ function GHAssigneesCell({
                     <Check className="size-3" />
                   ) : null}
                 </span>
-                {user.avatarUrl ? (
-                  <img src={user.avatarUrl} alt="" className="size-5 shrink-0 rounded-full" />
-                ) : (
-                  <span className="flex size-5 shrink-0 items-center justify-center rounded-full bg-muted text-[10px] font-medium text-muted-foreground">
-                    {user.login.slice(0, 1).toUpperCase()}
-                  </span>
-                )}
+                <GitHubUserAvatar
+                  login={user.login}
+                  name={user.name}
+                  avatarUrl={user.avatarUrl}
+                  className="size-5"
+                />
                 <span className="min-w-0 flex-1">
                   <span className="block truncate">{user.login}</span>
                   {user.name ? (
@@ -2388,13 +2376,12 @@ function PRReviewCell({
         <span className="flex size-4 shrink-0 items-center justify-center text-foreground">
           {selected ? <Check className="size-3.5" /> : null}
         </span>
-        {reviewer.avatarUrl ? (
-          <img src={reviewer.avatarUrl} alt="" className="size-5 shrink-0 rounded-full" />
-        ) : (
-          <span className="flex size-5 shrink-0 items-center justify-center rounded-full bg-muted text-[10px] font-medium text-muted-foreground">
-            {reviewer.login.slice(0, 1).toUpperCase()}
-          </span>
-        )}
+        <GitHubUserAvatar
+          login={reviewer.login}
+          name={reviewer.name}
+          avatarUrl={reviewer.avatarUrl}
+          className="size-5"
+        />
         <span className="min-w-0 flex-1">
           <span className="block truncate">
             <span className="font-semibold text-foreground">{reviewer.login}</span>
diff --git a/src/renderer/src/components/github/repro-8784-ghe-avatar-fallback.test.ts b/src/renderer/src/components/github/repro-8784-ghe-avatar-fallback.test.ts
index f30da28d603..533274b2a95 100644
--- a/src/renderer/src/components/github/repro-8784-ghe-avatar-fallback.test.ts
+++ b/src/renderer/src/components/github/repro-8784-ghe-avatar-fallback.test.ts
@@ -51,4 +51,68 @@ describe('issue #8784 GHE avatar fallback (regression)', () => {
     // Why: list chip must not hardcode github.com/{login}.png.
     expect(taskPage).not.toMatch(/github\.com\/\$\{reviewer\.login\}\.png/)
   })
+
+  // GHES URLs can exist but fail unauthenticated; target slots need onError fallbacks.
+  // Scope checks because TaskPage also renders non-GitHub provider avatars.
+  const GITHUB_AVATAR_SLOTS = [
+    {
+      file: 'pull-request-page/reviewers/picker-row.tsx',
+      fn: 'ReviewerPickerRow',
+      login: 'reviewer.login',
+      displayName: 'reviewer.name'
+    },
+    {
+      file: 'pull-request-page/conversation/comment-card.tsx',
+      fn: 'ConversationCommentCard',
+      login: 'comment.author',
+      displayName: null
+    },
+    {
+      file: 'pull-request-page/mentions/textarea.tsx',
+      fn: 'MentionTextarea',
+      login: 'option.login',
+      displayName: 'option.name'
+    },
+    {
+      file: 'TaskPage.tsx',
+      fn: 'GitHubAssigneeAvatar',
+      login: 'assignee.login',
+      displayName: 'assignee.name'
+    },
+    { file: 'TaskPage.tsx', fn: 'GHAssigneesCell', login: 'user.login', displayName: 'user.name' },
+    {
+      file: 'TaskPage.tsx',
+      fn: 'PRReviewCell',
+      login: 'reviewer.login',
+      displayName: 'reviewer.name'
+    }
+  ] as const
+
+  function componentBody(file: string, fn: string): string {
+    const source = readFileSync(join(__dirname, '..', file), 'utf8')
+    const start = source.indexOf(`function ${fn}`)
+    expect(start, `${file}: function ${fn} not found`).toBeGreaterThanOrEqual(0)
+    const next = source.indexOf('\nfunction ', start + 1)
+    return source.slice(start, next === -1 ? undefined : next)
+  }
+
+  it.each(GITHUB_AVATAR_SLOTS)(
+    'renders the $fn avatar through GitHubUserAvatar (#13976)',
+    ({ file, fn, login }) => {
+      const body = componentBody(file, fn)
+
+      // Reject aliases and resolver expressions as well as direct avatarUrl fields.
+      expect(body, `${fn} still renders a bare img`).not.toMatch(/<img[\s>]/)
+      expect(body, `${fn} does not use GitHubUserAvatar`).toContain('<GitHubUserAvatar')
+      expect(body, `${fn} does not pass its login`).toContain(`login={${login}}`)
+    }
+  )
+
+  // Preserve two-letter initials when the fallback renders.
+  it.each(GITHUB_AVATAR_SLOTS.filter((slot) => slot.displayName !== null))(
+    'passes the $fn display name so initials are not reduced to one letter (#13976)',
+    ({ file, fn, displayName }) => {
+      expect(componentBody(file, fn)).toContain(`name={${displayName}}`)
+    }
+  )
 })
diff --git a/src/renderer/src/components/pull-request-page/conversation/comment-card.tsx b/src/renderer/src/components/pull-request-page/conversation/comment-card.tsx
index 66ed253a6c3..598a23ad6ca 100644
--- a/src/renderer/src/components/pull-request-page/conversation/comment-card.tsx
+++ b/src/renderer/src/components/pull-request-page/conversation/comment-card.tsx
@@ -12,6 +12,7 @@ import {
 import { formatRelativeTime } from '@/components/github/work-item-state-presentation'
 import { CommentCodeContext } from '@/components/github/CommentCodeContext'
 import { CommentReactions } from '@/components/github/CommentReactions'
+import { GitHubUserAvatar } from '@/components/github/github-user-avatar'
 import { translate } from '@/i18n/i18n'
 import type { GitHubOwnerRepo, GitHubPRFile } from '../../../../../shared/github/pull-request-types'
 import type { PRComment } from '../../../../../shared/github/comment-types'
@@ -62,15 +63,12 @@ export function ConversationCommentCard({
       )}
     >
       <div className="flex min-w-0 items-center gap-2 border-b border-border/40 px-3 py-2">
-        {comment.authorAvatarUrl ? (
-          <img
-            src={comment.authorAvatarUrl}
-            alt={comment.author}
-            className="size-5 shrink-0 rounded-full"
-          />
-        ) : (
-          <div className="size-5 shrink-0 rounded-full bg-muted" />
-        )}
+        <GitHubUserAvatar
+          login={comment.author}
+          avatarUrl={comment.authorAvatarUrl}
+          title={comment.author}
+          className="size-5"
+        />
         <span
           className={cn(
             'min-w-0 truncate text-[13px] font-semibold',
diff --git a/src/renderer/src/components/pull-request-page/mentions/textarea.tsx b/src/renderer/src/components/pull-request-page/mentions/textarea.tsx
index 637acad4183..f272998204c 100644
--- a/src/renderer/src/components/pull-request-page/mentions/textarea.tsx
+++ b/src/renderer/src/components/pull-request-page/mentions/textarea.tsx
@@ -1,6 +1,7 @@
 import React, { useCallback, useId, useMemo, useState } from 'react'
 import { cn } from '@/lib/utils'
 import { filterGitHubMentionOptions } from '@/components/github/github-mention-option-filter'
+import { GitHubUserAvatar } from '@/components/github/github-user-avatar'
 import type { MentionOption, MentionQuery } from '../page-types'
 import { findMentionQuery } from './query'
 
@@ -86,13 +87,12 @@ export function MentionTextarea({
                 index === activeIndex && 'bg-accent text-accent-foreground'
               )}
             >
-              {option.avatarUrl ? (
-                <img src={option.avatarUrl} alt="" className="size-5 shrink-0 rounded-full" />
-              ) : (
-                <div className="flex size-5 shrink-0 items-center justify-center rounded-full bg-muted text-[10px] font-medium text-muted-foreground">
-                  {option.login.slice(0, 1).toUpperCase()}
-                </div>
-              )}
+              <GitHubUserAvatar
+                login={option.login}
+                name={option.name}
+                avatarUrl={option.avatarUrl}
+                className="size-5"
+              />
               <span className="flex min-w-0 flex-1 items-baseline gap-1.5">
                 <span className="shrink-0 font-medium">@{option.login}</span>
                 {option.name && (
diff --git a/src/renderer/src/components/pull-request-page/reviewers/picker-row.tsx b/src/renderer/src/components/pull-request-page/reviewers/picker-row.tsx
index a8b347765f2..5e24fffdbbb 100644
--- a/src/renderer/src/components/pull-request-page/reviewers/picker-row.tsx
+++ b/src/renderer/src/components/pull-request-page/reviewers/picker-row.tsx
@@ -2,6 +2,7 @@ import React from 'react'
 import { Check } from 'lucide-react'
 import { cn } from '@/lib/utils'
 import { translate } from '@/i18n/i18n'
+import { GitHubUserAvatar } from '@/components/github/github-user-avatar'
 import type { GitHubAssignableUser } from '../../../../../shared/github/pull-request-types'
 
 export function ReviewerPickerRow({
@@ -59,13 +60,12 @@ export function ReviewerPickerRow({
       <span className="flex size-4 shrink-0 items-center justify-center text-foreground">
         {selected ? <Check className="size-3.5" /> : null}
       </span>
-      {reviewer.avatarUrl ? (
-        <img src={reviewer.avatarUrl} alt="" className="size-5 shrink-0 rounded-full" />
-      ) : (
-        <span className="flex size-5 shrink-0 items-center justify-center rounded-full bg-muted text-[10px] font-medium text-muted-foreground">
-          {reviewer.login.slice(0, 1).toUpperCase()}
-        </span>
-      )}
+      <GitHubUserAvatar
+        login={reviewer.login}
+        name={reviewer.name}
+        avatarUrl={reviewer.avatarUrl}
+        className="size-5"
+      />
       <span className="min-w-0 flex-1">
         <span className="block truncate">
           <span className="font-semibold text-foreground">{reviewer.login}</span>