1 files changed, 18 insertions, 16 deletions
diff --git a/src/client/util/DragManager.ts b/src/client/util/DragManager.ts
index c35941ee5..cc116fb46 100644
--- a/src/client/util/DragManager.ts
+++ b/src/client/util/DragManager.ts
@@ -1,6 +1,6 @@
 import { action, observable, runInAction } from 'mobx';
 import { DateField } from '../../fields/DateField';
-import { Doc, Field, Opt } from '../../fields/Doc';
+import { Doc, Field, Opt, StrListCast } from '../../fields/Doc';
 import { List } from '../../fields/List';
 import { PrefetchProxy } from '../../fields/Proxy';
 import { listSpec } from '../../fields/Schema';
@@ -207,24 +207,26 @@ export namespace DragManager {
             dropEvent?.(); // glr: optional additional function to be called - in this case with presentation trails
             if (docDragData && !docDragData.droppedDocuments.length) {
                 docDragData.dropAction = dragData.userDropAction || dragData.dropAction;
-                docDragData.droppedDocuments = await Promise.all(
-                    dragData.draggedDocuments.map(async d =>
-                        !dragData.isDocDecorationMove && !dragData.userDropAction && ScriptCast(d.onDragStart)
-                            ? addAudioTag(ScriptCast(d.onDragStart).script.run({ this: d }).result)
-                            : docDragData.dropAction === 'alias'
-                            ? Doc.BestAlias(d)
-                            : docDragData.dropAction === 'proto'
-                            ? Doc.GetProto(d)
-                            : docDragData.dropAction === 'copy'
-                            ? (
-                                  await Doc.MakeClone(d)
-                              ).clone
-                            : d
+                docDragData.droppedDocuments = (
+                    await Promise.all(
+                        dragData.draggedDocuments.map(async d =>
+                            !dragData.isDocDecorationMove && !dragData.userDropAction && ScriptCast(d.onDragStart)
+                                ? addAudioTag(ScriptCast(d.onDragStart).script.run({ this: d }).result)
+                                : docDragData.dropAction === 'alias'
+                                ? Doc.BestAlias(d)
+                                : docDragData.dropAction === 'proto'
+                                ? Doc.GetProto(d)
+                                : docDragData.dropAction === 'copy'
+                                ? (
+                                      await Doc.MakeClone(d)
+                                  ).clone
+                                : d
+                        )
                     )
-                );
+                ).filter(d => d);
                 !['same', 'proto'].includes(docDragData.dropAction as any) &&
                     docDragData.droppedDocuments.forEach((drop: Doc, i: number) => {
-                        const dragProps = Cast(dragData.draggedDocuments[i].removeDropProperties, listSpec('string'), []);
+                        const dragProps = StrListCast(dragData.draggedDocuments[i].removeDropProperties);
                         const remProps = (dragData?.removeDropProperties || []).concat(Array.from(dragProps));
                         remProps.map(prop => (drop[prop] = undefined));
                     });