Merge remote-tracking branch 'origin/speedups2' into parker

1 files changed, 1 insertions, 2 deletions

diff --git a/src/client/util/UndoManager.ts b/src/client/util/UndoManager.ts
index 44e44d335..d1f1a0099 100644
--- a/src/client/util/UndoManager.ts
+++ b/src/client/util/UndoManager.ts
@@ -1,5 +1,4 @@
 import { observable, action, runInAction } from "mobx";
-import 'source-map-support/register';
 import { Without } from "../../Utils";
 
 function getBatchName(target: any, key: string | symbol): string {
@@ -107,7 +106,7 @@ export namespace UndoManager {
     }
     export function FilterBatches(fieldTypes: string[]) {
         const fieldCounts: { [key: string]: number } = {};
-        const lastStack = UndoManager.undoStack.lastElement();
+        const lastStack = UndoManager.undoStack.slice(-1)[0];//.lastElement();
         if (lastStack) {
             lastStack.forEach(ev => fieldTypes.includes(ev.prop) && (fieldCounts[ev.prop] = (fieldCounts[ev.prop] || 0) + 1));
             const fieldCount2: { [key: string]: number } = {};