fixed dragging documents to bottom of presentation list. fixed adding to preentation list without creatinga a duplicate.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/client/views/collections/CollectionStackingView.tsx b/src/client/views/collections/CollectionStackingView.tsx
index d490b65a8..4880d342c 100644
--- a/src/client/views/collections/CollectionStackingView.tsx
+++ b/src/client/views/collections/CollectionStackingView.tsx
@@ -295,7 +295,7 @@ export class CollectionStackingView extends CollectionSubView<StackingDocument,
                 DragManager.docsBeingDragged = [];
                 if (docs && newDocs.length) {
                     const insertInd = dropInd === -1 ? docs.length : dropInd + dropAfter;
-                    const offset = newDocs.reduce((off, ndoc) => this.filteredChildren.find((fdoc, i) => ndoc === fdoc && i <= insertInd) ? off + 1 : off, 0);
+                    const offset = newDocs.reduce((off, ndoc) => this.filteredChildren.find((fdoc, i) => ndoc === fdoc && i < insertInd) ? off + 1 : off, 0);
                     newDocs.filter(ndoc => docs.indexOf(ndoc) !== -1).forEach(ndoc => docs.splice(docs.indexOf(ndoc), 1));
                     docs.splice(insertInd - offset, 0, ...newDocs);
                 }