From a608da9179c945cb840618033c1584073da1bd2a Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 15 Jul 2026 19:36:40 +0000
Subject: [PATCH 1/2] Initial plan


From 3db60ad8c118b499e2a196fe9af0e01eabf1ff4d Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 15 Jul 2026 19:45:35 +0000
Subject: [PATCH 2/2] Grid utils: normalize invalid selection range values

---
 packages/devextreme/js/__internal/grids/grid_core/m_utils.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/devextreme/js/__internal/grids/grid_core/m_utils.ts b/packages/devextreme/js/__internal/grids/grid_core/m_utils.ts
index f03a205a92c4..8f612e289a62 100644
--- a/packages/devextreme/js/__internal/grids/grid_core/m_utils.ts
+++ b/packages/devextreme/js/__internal/grids/grid_core/m_utils.ts
@@ -566,8 +566,8 @@ export default {
     try {
       if (focusedElement) {
         return {
-          selectionStart: focusedElement.selectionStart,
-          selectionEnd: focusedElement.selectionEnd,
+          selectionStart: isNumeric(focusedElement.selectionStart) ? focusedElement.selectionStart : -1,
+          selectionEnd: isNumeric(focusedElement.selectionEnd) ? focusedElement.selectionEnd : -1,
         };
       }
     } catch (e) { /* empty */ }