fix issue with undo because this.elem was overwritten with node.remove()

editor/extensions/ext-connector.js

@@ -573,18 +573,19 @@ export default {
       },
       elementChanged (opts) {
         let elem = opts.elems[0];
-        if (elem && elem.tagName === 'svg' && elem.id === 'svgcontent') {
+        if (!elem) return;
+        if (elem.tagName === 'svg' && elem.id === 'svgcontent') {
           // Update svgcontent (can change on import)
           svgcontent = elem;
           init();
         }
 
         // Has marker, so change offset
-        if (elem && (
+        if (
           elem.getAttribute('marker-start') ||
           elem.getAttribute('marker-mid') ||
           elem.getAttribute('marker-end')
-        )) {
+        ) {
           const start = elem.getAttribute('marker-start');
           const mid = elem.getAttribute('marker-mid');
           const end = elem.getAttribute('marker-end');

editor/history.js

@@ -223,7 +223,7 @@ export class InsertElementCommand extends Command {
     }
 
     this.parent = this.elem.parentNode;
-    this.elem = this.elem.remove();
+    this.elem.remove();
 
     if (handler) {
       handler.handleHistoryEvent(HistoryEventTypes.AFTER_UNAPPLY, this);
@@ -280,7 +280,7 @@ export class RemoveElementCommand extends Command {
 
     removeElementFromListMap(this.elem);
     this.parent = this.elem.parentNode;
-    this.elem = this.elem.remove();
+    this.elem.remove();
 
     if (handler) {
       handler.handleHistoryEvent(HistoryEventTypes.AFTER_APPLY, this);

editor/svgcanvas.js

@@ -516,7 +516,7 @@ const undoMgr = canvas.undoMgr = new UndoManager({
         } else if (!isApply) {
           restoreRefElems(cmd.elem);
         }
-        if (cmd.elem.tagName === 'use') {
+        if (cmd.elem && cmd.elem.tagName === 'use') {
           setUseData(cmd.elem);
         }
       } else if (cmdType === ChangeElementCommand.type()) {