From 06f49cf0e55d111622b777d54cbde35802c96bb7 Mon Sep 17 00:00:00 2001
From: Olivier Tassinari <olivier.tassinari@gmail.com>
Date: Fri, 30 Dec 2022 15:51:32 +0100
Subject: [PATCH 1/2] [core] Handle selecton edge case

---
 .../src/hooks/features/clipboard/useGridClipboard.ts | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/packages/grid/x-data-grid/src/hooks/features/clipboard/useGridClipboard.ts b/packages/grid/x-data-grid/src/hooks/features/clipboard/useGridClipboard.ts
index 69d9b33957f6..8b5f400a9c46 100644
--- a/packages/grid/x-data-grid/src/hooks/features/clipboard/useGridClipboard.ts
+++ b/packages/grid/x-data-grid/src/hooks/features/clipboard/useGridClipboard.ts
@@ -26,15 +26,15 @@ function writeToClipboardPolyfill(data: string) {
 }
 
 function hasNativeSelection(element: HTMLInputElement) {
-  if (window.getSelection()?.toString() !== '') {
+  // When getSelection is called on an <iframe> that is not displayed Firefox will return null.
+  if (window.getSelection() && window.getSelection()!.toString() !== '') {
     return true;
   }
 
-  if (!element) {
-    return false;
-  }
-
-  if ((element.selectionEnd || 0) - (element.selectionStart || 0) > 0) {
+  // window.getSelection() returns an empty string in Firefox for selections inside a form element.
+  // See: https://bugzilla.mozilla.org/show_bug.cgi?id=85686.
+  // Instead, we can use element.selectionStart that is only defined on form elements.
+  if (element && (element.selectionEnd || 0) - (element.selectionStart || 0) > 0) {
     return true;
   }
 

From 6e28144b2d076a655bc2d612609e00edb7fefd7c Mon Sep 17 00:00:00 2001
From: Olivier Tassinari <olivier.tassinari@gmail.com>
Date: Mon, 2 Jan 2023 13:03:39 +0100
Subject: [PATCH 2/2] simpler version

Signed-off-by: Olivier Tassinari <olivier.tassinari@gmail.com>
---
 .../src/hooks/features/clipboard/useGridClipboard.ts            | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/grid/x-data-grid/src/hooks/features/clipboard/useGridClipboard.ts b/packages/grid/x-data-grid/src/hooks/features/clipboard/useGridClipboard.ts
index 8b5f400a9c46..7698e67972bc 100644
--- a/packages/grid/x-data-grid/src/hooks/features/clipboard/useGridClipboard.ts
+++ b/packages/grid/x-data-grid/src/hooks/features/clipboard/useGridClipboard.ts
@@ -27,7 +27,7 @@ function writeToClipboardPolyfill(data: string) {
 
 function hasNativeSelection(element: HTMLInputElement) {
   // When getSelection is called on an <iframe> that is not displayed Firefox will return null.
-  if (window.getSelection() && window.getSelection()!.toString() !== '') {
+  if (window.getSelection()?.toString()) {
     return true;
   }