From 1be496f0a61bf7c1da912caab62804e5e173ca5b Mon Sep 17 00:00:00 2001
From: Bao Nguyen <39545125+giaBaoJS@users.noreply.github.com>
Date: Mon, 24 Aug 2026 20:14:16 +0700
Subject: [PATCH] fix: accept `onfocusin`/`onfocusout` in
 `a11y_mouse_events_have_key_events` (#18689)

Fixes #8089

focusin/focusout are the bubble variants of focus/blur

---------

Co-authored-by: Simon H <5968653+dummdidumm@users.noreply.github.com>
---
 .changeset/large-schools-smell.md                |  5 +++++
 .../98-reference/.generated/compile-warnings.md  |  2 +-
 .../svelte/messages/compile-warnings/a11y.md     |  2 +-
 .../2-analyze/visitors/shared/a11y/index.js      | 16 ++++++++++++++--
 .../input.svelte                                 |  4 ++++
 5 files changed, 25 insertions(+), 4 deletions(-)
 create mode 100644 .changeset/large-schools-smell.md

diff --git a/.changeset/large-schools-smell.md b/.changeset/large-schools-smell.md
new file mode 100644
index 0000000000..61ef571f02
--- /dev/null
+++ b/.changeset/large-schools-smell.md
@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: accept `onfocusin`/`onfocusout` in `a11y_mouse_events_have_key_events`
diff --git a/documentation/docs/98-reference/.generated/compile-warnings.md b/documentation/docs/98-reference/.generated/compile-warnings.md
index f372a010a5..237ec105f6 100644
--- a/documentation/docs/98-reference/.generated/compile-warnings.md
+++ b/documentation/docs/98-reference/.generated/compile-warnings.md
@@ -360,7 +360,7 @@ Enforce that heading elements (`h1`, `h2`, etc.) and anchors have content and th
 '%event%' event must be accompanied by '%accompanied_by%' event
 ```
 
-Enforce that `onmouseover` and `onmouseout` are accompanied by `onfocus` and `onblur`, respectively. This helps to ensure that any functionality triggered by these mouse events is also accessible to keyboard users.
+Enforce that `onmouseover` and `onmouseout` are accompanied by `onfocus` (or `onfocusin`) and `onblur` (or `onfocusout`), respectively. This helps to ensure that any functionality triggered by these mouse events is also accessible to keyboard users.
 
 ```svelte
 <!-- A11y: onmouseover must be accompanied by onfocus -->
diff --git a/packages/svelte/messages/compile-warnings/a11y.md b/packages/svelte/messages/compile-warnings/a11y.md
index 1f48ef0dd5..915032bb93 100644
--- a/packages/svelte/messages/compile-warnings/a11y.md
+++ b/packages/svelte/messages/compile-warnings/a11y.md
@@ -300,7 +300,7 @@ Enforce that heading elements (`h1`, `h2`, etc.) and anchors have content and th
 
 > '%event%' event must be accompanied by '%accompanied_by%' event
 
-Enforce that `onmouseover` and `onmouseout` are accompanied by `onfocus` and `onblur`, respectively. This helps to ensure that any functionality triggered by these mouse events is also accessible to keyboard users.
+Enforce that `onmouseover` and `onmouseout` are accompanied by `onfocus` (or `onfocusin`) and `onblur` (or `onfocusout`), respectively. This helps to ensure that any functionality triggered by these mouse events is also accessible to keyboard users.
 
 ```svelte
 <!-- A11y: onmouseover must be accompanied by onfocus -->
diff --git a/packages/svelte/src/compiler/phases/2-analyze/visitors/shared/a11y/index.js b/packages/svelte/src/compiler/phases/2-analyze/visitors/shared/a11y/index.js
index a6e801cf5a..e09ab018a8 100644
--- a/packages/svelte/src/compiler/phases/2-analyze/visitors/shared/a11y/index.js
+++ b/packages/svelte/src/compiler/phases/2-analyze/visitors/shared/a11y/index.js
@@ -373,11 +373,23 @@ export function check_element(node, context) {
 		}
 	}
 
-	if (!has_spread && handlers.has('mouseover') && !handlers.has('focus')) {
+	// `focus`/`blur` don't bubble, so an element that isn't focusable itself can only be notified
+	// about focus changes inside it through `focusin`/`focusout` — accept those as well
+	if (
+		!has_spread &&
+		handlers.has('mouseover') &&
+		!handlers.has('focus') &&
+		!handlers.has('focusin')
+	) {
 		w.a11y_mouse_events_have_key_events(node, 'mouseover', 'focus');
 	}
 
-	if (!has_spread && handlers.has('mouseout') && !handlers.has('blur')) {
+	if (
+		!has_spread &&
+		handlers.has('mouseout') &&
+		!handlers.has('blur') &&
+		!handlers.has('focusout')
+	) {
 		w.a11y_mouse_events_have_key_events(node, 'mouseout', 'blur');
 	}
 
diff --git a/packages/svelte/tests/validator/samples/a11y-mouse-events-have-key-events/input.svelte b/packages/svelte/tests/validator/samples/a11y-mouse-events-have-key-events/input.svelte
index f9fe4f15c1..85e9384c98 100644
--- a/packages/svelte/tests/validator/samples/a11y-mouse-events-have-key-events/input.svelte
+++ b/packages/svelte/tests/validator/samples/a11y-mouse-events-have-key-events/input.svelte
@@ -17,3 +17,7 @@
 <div onmouseout={() => {}} onblur={() => {}}></div>
 <!-- svelte-ignore a11y_no_static_element_interactions -->
 <div onmouseout={() => {}} {...otherProps}></div>
+<!-- svelte-ignore a11y_no_static_element_interactions -->
+<div onmouseover={() => {}} onfocusin={() => {}}></div>
+<!-- svelte-ignore a11y_no_static_element_interactions -->
+<div onmouseout={() => {}} onfocusout={() => {}}></div>