From 1b54e506a44420d0c8a9e000cf45b1c4f5e33026 Mon Sep 17 00:00:00 2001
From: Christian Patzl <75803401+Christiano300@users.noreply.github.com>
Date: Thu, 5 Dec 2024 04:27:07 +0100
Subject: [PATCH] fix(html): allow unexpected question mark in tag name
 (#18852)

---
 packages/vite/src/node/plugins/html.ts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/packages/vite/src/node/plugins/html.ts b/packages/vite/src/node/plugins/html.ts
index 0a10d8c8fe387e..25a23e98c7a7d0 100644
--- a/packages/vite/src/node/plugins/html.ts
+++ b/packages/vite/src/node/plugins/html.ts
@@ -308,6 +308,10 @@ function handleParseError(
     case 'non-void-html-element-start-tag-with-trailing-solidus':
       // Allow self closing on non-void elements #10439
       return
+    case 'unexpected-question-mark-instead-of-tag-name':
+      // Allow <?xml> declaration and <?> empty elements
+      // lit generates <?>: https://github.com/lit/lit/issues/2470
+      return
   }
   const parseError = formatParseError(parserError, filePath, html)
   throw new Error(