diff --git a/core/block_svg.ts b/core/block_svg.ts
index 1b85d38ce6b..43fe163c799 100644
--- a/core/block_svg.ts
+++ b/core/block_svg.ts
@@ -300,9 +300,12 @@ export class BlockSvg
 
     const oldXY = this.getRelativeToSurfaceXY();
     const focusedNode = getFocusManager().getFocusedNode();
-    const restoreFocus = this.getSvgRoot().contains(
-      focusedNode?.getFocusableElement() ?? null,
-    );
+    let element = focusedNode?.getFocusableElement() ?? null;
+    // Make sure the element is of Node type
+    if (!(element instanceof Node)) {
+      element = null;
+    }
+    const restoreFocus = this.getSvgRoot().contains(element);
     if (newParent) {
       (newParent as BlockSvg).getSvgRoot().appendChild(svgRoot);
       // appendChild() clears focus state, so re-focus the previously focused
@@ -870,11 +873,12 @@ export class BlockSvg
     // If this block (or a descendant) was focused, focus its parent or
     // workspace instead.
     const focusManager = getFocusManager();
-    if (
-      this.getSvgRoot().contains(
-        focusManager.getFocusedNode()?.getFocusableElement() ?? null,
-      )
-    ) {
+    let element = focusManager.getFocusedNode()?.getFocusableElement() ?? null;
+    // Make sure the element is of Node type
+    if (!(element instanceof Node)) {
+      element = null;
+    }
+    if (this.getSvgRoot().contains(element)) {
       let parent: BlockSvg | undefined | null = this.getParent();
       if (!parent) {
         // In some cases, blocks are disconnected from their parents before
diff --git a/core/focus_manager.ts b/core/focus_manager.ts
index 02e0591070f..21716be1058 100644
--- a/core/focus_manager.ts
+++ b/core/focus_manager.ts
@@ -320,13 +320,18 @@ export class FocusManager {
       this.isUpdatingFocusedNode = true;
     }
 
-    // Double check that state wasn't desynchronized in the background. See:
-    // https://github.com/google/blockly-keyboard-experimentation/issues/87.
-    // This is only done for the case where the same node is being focused twice
-    // since other cases should automatically correct (due to the rest of the
-    // routine running as normal).
-    const prevFocusedElement = this.focusedNode?.getFocusableElement();
-    const hasDesyncedState = prevFocusedElement !== document.activeElement;
+    // // TODO: This will break multiselect plugin as it will make the
+    // // selected `MultiselectDraggable` (has already assigned to `this.focusedNode`)
+    // // to lose focus (get changed to the actual focused one managed by Blockly core).
+    // // Double check that state wasn't desynchronized in the background. See:
+    // // https://github.com/google/blockly-keyboard-experimentation/issues/87.
+    // // This is only done for the case where the same node is being focused twice
+    // // since other cases should automatically correct (due to the rest of the
+    // // routine running as normal).
+    // const prevFocusedElement = this.focusedNode?.getFocusableElement();
+    // const hasDesyncedState = prevFocusedElement !== document.activeElement;
+    const hasDesyncedState = false;
+
     if (this.focusedNode === focusableNode && !hasDesyncedState) {
       if (mustRestoreUpdatingNode) {
         // Reenable state syncing from DOM events.
diff --git a/core/layer_manager.ts b/core/layer_manager.ts
index fd7d8fe235a..48d3053103b 100644
--- a/core/layer_manager.ts
+++ b/core/layer_manager.ts
@@ -4,7 +4,6 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-import {getFocusManager} from './focus_manager.js';
 import type {IFocusableNode} from './interfaces/i_focusable_node.js';
 import {IRenderedElement} from './interfaces/i_rendered_element.js';
 import * as layerNums from './layers.js';
@@ -104,11 +103,14 @@ export class LayerManager {
   moveToDragLayer(elem: IRenderedElement & IFocusableNode) {
     this.dragLayer?.appendChild(elem.getSvgRoot());
 
-    if (elem.canBeFocused()) {
-      // Since moving the element to the drag layer will cause it to lose focus,
-      // ensure it regains focus (to ensure proper highlights & sent events).
-      getFocusManager().focusNode(elem);
-    }
+    // // TODO: This will break multiselect plugin, as multiselect plugin will
+    // // implicitly call this method as well, we should not change the focus to individual
+    // // block and move away from `MultiselectDraggable` at this time.
+    // if (elem.canBeFocused()) {
+    //   // Since moving the element to the drag layer will cause it to lose focus,
+    //   // ensure it regains focus (to ensure proper highlights & sent events).
+    //   getFocusManager().focusNode(elem);
+    // }
   }
 
   /**
@@ -119,11 +121,14 @@ export class LayerManager {
   moveOffDragLayer(elem: IRenderedElement & IFocusableNode, layerNum: number) {
     this.append(elem, layerNum);
 
-    if (elem.canBeFocused()) {
-      // Since moving the element off the drag layer will cause it to lose focus,
-      // ensure it regains focus (to ensure proper highlights & sent events).
-      getFocusManager().focusNode(elem);
-    }
+    // // TODO: This will break multiselect plugin, as multiselect plugin will
+    // // implicitly call this method as well, we should not change the focus to individual
+    // // block and move away from `MultiselectDraggable` at this time.
+    // if (elem.canBeFocused()) {
+    //   // Since moving the element off the drag layer will cause it to lose focus,
+    //   // ensure it regains focus (to ensure proper highlights & sent events).
+    //   getFocusManager().focusNode(elem);
+    // }
   }
 
   /**
diff --git a/core/utils/dom.ts b/core/utils/dom.ts
index 4087984151c..d400047a7cf 100644
--- a/core/utils/dom.ts
+++ b/core/utils/dom.ts
@@ -76,10 +76,16 @@ export function createSvgElement<T extends SVGElement>(
  */
 export function addClass(element: Element, className: string): boolean {
   const classNames = className.split(' ');
-  if (classNames.every((name) => element.classList.contains(name))) {
+  if (
+    classNames.every(
+      (name) => !!element.classList && element.classList.contains(name),
+    )
+  ) {
     return false;
   }
-  element.classList.add(...classNames);
+  if (element.classList) {
+    element.classList.add(...classNames);
+  }
   return true;
 }
 
@@ -90,7 +96,9 @@ export function addClass(element: Element, className: string): boolean {
  * @param classNames A string of one or multiple class names for an element.
  */
 export function removeClasses(element: Element, classNames: string) {
-  element.classList.remove(...classNames.split(' '));
+  if (element.classList) {
+    element.classList.remove(...classNames.split(' '));
+  }
 }
 
 /**
@@ -104,10 +112,16 @@ export function removeClasses(element: Element, classNames: string) {
  */
 export function removeClass(element: Element, className: string): boolean {
   const classNames = className.split(' ');
-  if (classNames.every((name) => !element.classList.contains(name))) {
+  if (
+    classNames.every(
+      (name) => !element.classList || !element.classList.contains(name),
+    )
+  ) {
     return false;
   }
-  element.classList.remove(...classNames);
+  if (element.classList) {
+    element.classList.remove(...classNames);
+  }
   return true;
 }
 
@@ -119,7 +133,7 @@ export function removeClass(element: Element, className: string): boolean {
  * @returns True if class exists, false otherwise.
  */
 export function hasClass(element: Element, className: string): boolean {
-  return element.classList.contains(className);
+  return !!element.classList && element.classList.contains(className);
 }
 
 /**