fixed crash in presbox

1 files changed, 1 insertions, 1 deletions

diff --git a/src/client/views/nodes/trails/PresBox.tsx b/src/client/views/nodes/trails/PresBox.tsx
index 048a033ee..6a929ef80 100644
--- a/src/client/views/nodes/trails/PresBox.tsx
+++ b/src/client/views/nodes/trails/PresBox.tsx
@@ -146,7 +146,7 @@ export class PresBox extends ViewBoxBaseComponent<FieldViewProps>() {
     @computed get selectedDoc() {
         return this.selectedDocumentView?.rootDoc;
     }
-    isActiveItemTarget = (layoutDoc: Doc) => this.activeItem.presentationTargetDoc === layoutDoc;
+    isActiveItemTarget = (layoutDoc: Doc) => this.activeItem?.presentationTargetDoc === layoutDoc;
     clearSelectedArray = () => this.selectedArray.clear();
     addToSelectedArray = (doc: Doc) => this.selectedArray.add(doc);
     removeFromSelectedArray = (doc: Doc) => this.selectedArray.delete(doc);