fix update of colorpickers

src/editor/panels/BottomPanelHandlers.js

@@ -17,13 +17,25 @@ class BottomPanelHandlers {
     this.editor = editor;
     this.svgCanvas = editor.canvas;
   }
+  /**
+   * @type {module}
+   */
+  get selectedElement () {
+    return this.editor.selectedElement;
+  }
+  /**
+   * @type {module}
+   */
+  get multiselected () {
+    return this.editor.multiselected;
+  }
 
   /**
   * @type {module}
   */
   changeStrokeWidth (e) {
     let val = e.target.value;
-    if (val === 0 && this.editor.selectedElement && ['line', 'polyline'].includes(this.editor.selectedElement.nodeName)) {
+    if (val === 0 && this.selectedElement && ['line', 'polyline'].includes(this.selectedElement.nodeName)) {
       val = 1;
     }
     this.svgCanvas.setStrokeWidth(val);

src/editor/panels/TopPanelHandlers.js

@@ -316,7 +316,7 @@ class TopPanelHandlers {
   * @returns {void}
   */
   clickUndo () {
-    const {undoMgr} = this.editor;
+    const {undoMgr} = this.editor.canvas;
     if (undoMgr.getUndoStackSize() > 0) {
       undoMgr.undo();
       this.editor.layersPanel.populateLayers();