diff --git a/l4d2web/static/js/files-overlay.js b/l4d2web/static/js/files-overlay.js
index 3740f1c..d3c500a 100644
--- a/l4d2web/static/js/files-overlay.js
+++ b/l4d2web/static/js/files-overlay.js
@@ -890,17 +890,30 @@
         return;
       }
 
-      // External drop — collect entries via webkitGetAsEntry if available,
-      // else fall back to flat dataTransfer.files.
+      // External drop — collect entries via webkitGetAsEntry where it
+      // returns an Entry (real OS drag with folder support), and fall back
+      // to getAsFile() for any item whose entry is null (synthetic events,
+      // browsers without the API, or items that have no folder structure).
       const items = event.dataTransfer.items;
       const files = [];
       const tasks = [];
-      if (items && items[0] && typeof items[0].webkitGetAsEntry === "function") {
+      if (items && items.length) {
         for (let i = 0; i < items.length; i++) {
-          const entry = items[i].webkitGetAsEntry();
-          if (entry) tasks.push(walkEntry(entry, "", files));
+          const item = items[i];
+          if (typeof item.webkitGetAsEntry === "function") {
+            const entry = item.webkitGetAsEntry();
+            if (entry) {
+              tasks.push(walkEntry(entry, "", files));
+              continue;
+            }
+          }
+          // Fallback: treat as a flat file.
+          if (typeof item.getAsFile === "function") {
+            const f = item.getAsFile();
+            if (f) files.push({ file: f, rel: f.name });
+          }
         }
-      } else {
+      } else if (event.dataTransfer.files) {
         for (let i = 0; i < event.dataTransfer.files.length; i++) {
           files.push({ file: event.dataTransfer.files[i], rel: event.dataTransfer.files[i].name });
         }