From dbddfe6cda850636c7ef49388773254963e74aa5 Mon Sep 17 00:00:00 2001
From: AnnMarueW <amward@fastmail.com>
Date: Fri, 24 Jul 2026 08:36:25 -0700
Subject: [PATCH 1/2] Fix multiple file drag-and-drop in dcc.Upload

---
 .../src/fragments/Upload.react.js             | 35 ++++++++++++-------
 1 file changed, 22 insertions(+), 13 deletions(-)

diff --git a/components/dash-core-components/src/fragments/Upload.react.js b/components/dash-core-components/src/fragments/Upload.react.js
index 0e6b66e30b..62def2927f 100644
--- a/components/dash-core-components/src/fragments/Upload.react.js
+++ b/components/dash-core-components/src/fragments/Upload.react.js
@@ -111,25 +111,34 @@ export default class Upload extends Component {
         // Handle drag-and-drop with folder support when multiple=true
         if (event.dataTransfer && event.dataTransfer.items) {
             const items = Array.from(event.dataTransfer.items);
+
+            // Get all entries synchronously before the first await
+            const entries = [];
             const files = [];
 
             for (const item of items) {
-                if (item.kind === 'file') {
-                    const entry = item.webkitGetAsEntry
-                        ? item.webkitGetAsEntry()
-                        : null;
-                    if (entry) {
-                        const entryFiles = await this.traverseFileTree(entry);
-                        files.push(...entryFiles);
-                    } else {
-                        // Fallback for browsers without webkitGetAsEntry
-                        const file = item.getAsFile();
-                        if (file) {
-                            files.push(file);
-                        }
+                if (item.kind !== 'file') {
+                    continue;
+                }
+
+                const entry = item.webkitGetAsEntry
+                    ? item.webkitGetAsEntry()
+                    : null;
+                if (entry) {
+                    entries.push(entry);
+                } else {
+                    // Fallback for browsers without webkitGetAsEntry
+                    const file = item.getAsFile();
+                    if (file) {
+                        files.push(file);
                     }
                 }
             }
+            // Process all entries after collecting them
+            for (const entry of entries) {
+                const entryFiles = await this.traverseFileTree(entry);
+                files.push(...entryFiles);
+            }
             return files;
         }
 

From 0d912b7850c9c6d3d74db4a32e77f76d3dd2ff6e Mon Sep 17 00:00:00 2001
From: AnnMarueW <amward@fastmail.com>
Date: Tue, 28 Jul 2026 08:01:28 -0700
Subject: [PATCH 2/2] added changelog

---
 CHANGELOG.md | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5c4cff63c9..fc0af57c54 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,9 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 ### Removed
 - [#3646](https://github.com/plotly/dash/pull/3646) Remove React 16 support (`16.14.0` is no longer an accepted value for `REACT_VERSION` / `_set_react_version`).
 
+### Fixed
+- [#3916](https://github.com/plotly/dash/pull/3916) Fixed a regression where dragging multiple files into `dcc.Upload` would upload only the first file when `multiple=True`
+
 ## [4.4.1] - 2026-07-21
 
 ## Fixed