From 76af4c2ef7c2aed6c49384b79de465b1b45cc52b Mon Sep 17 00:00:00 2001
From: amachang <seijro@gmail.com>
Date: Wed, 30 Jul 2025 16:31:29 +0900
Subject: [PATCH 1/2] test(compiler-dom): add failing tests for Chrome 134+
 HTML nesting

Add tests for new HTML5 specifications that allow:
- button as child of select
- inline elements (span, b, i, strong, em) as children of option

ref #13608
---
 .../transforms/validateHtmlNesting.spec.ts    | 48 +++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/packages/compiler-dom/__tests__/transforms/validateHtmlNesting.spec.ts b/packages/compiler-dom/__tests__/transforms/validateHtmlNesting.spec.ts
index 46d69846bae..86b8e7d3472 100644
--- a/packages/compiler-dom/__tests__/transforms/validateHtmlNesting.spec.ts
+++ b/packages/compiler-dom/__tests__/transforms/validateHtmlNesting.spec.ts
@@ -27,6 +27,31 @@ describe('validate html nesting', () => {
     })
     expect(err).toBeUndefined()
   })
+
+  // #13608 - Chrome 134+ HTML5 spec updates
+  it('should not warn with select > button', () => {
+    let err: CompilerError | undefined
+    compile(`<select><button>Click me</button></select>`, {
+      onWarn: e => (err = e),
+    })
+    expect(err).toBeUndefined()
+  })
+
+  it('should not warn with option > span', () => {
+    let err: CompilerError | undefined
+    compile(`<select><option><span>Styled text</span></option></select>`, {
+      onWarn: e => (err = e),
+    })
+    expect(err).toBeUndefined()
+  })
+
+  it('should not warn with option > b', () => {
+    let err: CompilerError | undefined
+    compile(`<select><option><b>Bold text</b></option></select>`, {
+      onWarn: e => (err = e),
+    })
+    expect(err).toBeUndefined()
+  })
 })
 
 /**
@@ -148,6 +173,29 @@ describe('isValidHTMLNesting', () => {
     expect(isValidHTMLNesting('h1', 'div')).toBe(true)
   })
 
+  test('select - Chrome 134+ allows button as child', () => {
+    // These should be valid according to new HTML5 spec (Chrome 134+)
+    expect(isValidHTMLNesting('select', 'button')).toBe(true)
+
+    // Traditional valid children should still work
+    expect(isValidHTMLNesting('select', 'option')).toBe(true)
+    expect(isValidHTMLNesting('select', 'optgroup')).toBe(true)
+    expect(isValidHTMLNesting('select', 'hr')).toBe(true)
+  })
+
+  test('option - Chrome 134+ allows styled content', () => {
+    // These should be valid according to new HTML5 spec (Chrome 134+)
+    expect(isValidHTMLNesting('option', 'span')).toBe(true)
+    expect(isValidHTMLNesting('option', 'b')).toBe(true)
+    expect(isValidHTMLNesting('option', 'i')).toBe(true)
+    expect(isValidHTMLNesting('option', 'strong')).toBe(true)
+    expect(isValidHTMLNesting('option', 'em')).toBe(true)
+
+    // Block-level elements might still be invalid
+    expect(isValidHTMLNesting('option', 'div')).toBe(false)
+    expect(isValidHTMLNesting('option', 'p')).toBe(false)
+  })
+
   describe('SVG', () => {
     test('svg', () => {
       // invalid non-svg tags as children

From 22876fe69a0050e501cf3e5e1920050a202d1f93 Mon Sep 17 00:00:00 2001
From: amachang <seijro@gmail.com>
Date: Wed, 30 Jul 2025 16:38:55 +0900
Subject: [PATCH 2/2] fix(compiler-dom): update HTML nesting validation for
 Chrome 134+

Allow new HTML5 nesting patterns:
- button as child of select
- inline elements (span, b, i, strong, em) as children of option

This aligns with the latest HTML specifications supported in Chrome 134+
while maintaining validation for invalid block-level elements.

close #13608
---
 packages/compiler-dom/src/htmlNesting.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/compiler-dom/src/htmlNesting.ts b/packages/compiler-dom/src/htmlNesting.ts
index 5f924880bd0..09861eb68b3 100644
--- a/packages/compiler-dom/src/htmlNesting.ts
+++ b/packages/compiler-dom/src/htmlNesting.ts
@@ -63,7 +63,7 @@ const onlyValidChildren: Record<string, Set<string>> = {
     'template',
   ]),
   optgroup: new Set(['option']),
-  select: new Set(['optgroup', 'option', 'hr']),
+  select: new Set(['optgroup', 'option', 'hr', 'button']),
   // table
   table: new Set(['caption', 'colgroup', 'tbody', 'tfoot', 'thead']),
   tr: new Set(['td', 'th']),
@@ -74,7 +74,6 @@ const onlyValidChildren: Record<string, Set<string>> = {
   // these elements can not have any children elements
   script: emptySet,
   iframe: emptySet,
-  option: emptySet,
   textarea: emptySet,
   style: emptySet,
   title: emptySet,
@@ -108,6 +107,7 @@ const onlyValidParents: Record<string, Set<string>> = {
 
 /** maps element to set of elements that can not be it's children, others can */
 const knownInvalidChildren: Record<string, Set<string>> = {
+  option: new Set(['div', 'p']),
   p: new Set([
     'address',
     'article',