From 55da67e9aa4d8a66f5a68e4b60d2e253b01cc244 Mon Sep 17 00:00:00 2001
From: Dmitry_Platonov <platonovd32@gmail.com>
Date: Sat, 21 May 2022 07:48:44 +0200
Subject: [PATCH] Set 'dropEffect' based on 'effectAllowed' for drag-and-drop
 in the viewer (issue 14942). See
 https://developer.mozilla.org/en-US/docs/Web/API/DataTransfer/effectAllowed

---
 web/app.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/web/app.js b/web/app.js
index bb4808b26..f33a82d95 100644
--- a/web/app.js
+++ b/web/app.js
@@ -2187,7 +2187,8 @@ function webViewerInitialized() {
     appConfig.mainContainer.addEventListener("dragover", function (evt) {
       evt.preventDefault();
 
-      evt.dataTransfer.dropEffect = "move";
+      evt.dataTransfer.dropEffect =
+        evt.dataTransfer.effectAllowed === "copy" ? "copy" : "move";
     });
     appConfig.mainContainer.addEventListener("drop", function (evt) {
       evt.preventDefault();