diff --git a/src/component/mxgraph/GraphCellUpdater.ts b/src/component/mxgraph/GraphCellUpdater.ts
index 37cbbdb12c..5291d15694 100644
--- a/src/component/mxgraph/GraphCellUpdater.ts
+++ b/src/component/mxgraph/GraphCellUpdater.ts
@@ -39,7 +39,11 @@ export function newGraphCellUpdater(graph: BpmnGraph, cssRegistry: CssRegistry):
  * @internal
  */
 export default class GraphCellUpdater {
-  constructor(readonly graph: BpmnGraph, readonly overlayConverter: OverlayConverter, readonly styleManager: StyleManager) {}
+  constructor(readonly graph: BpmnGraph, readonly overlayConverter: OverlayConverter, private readonly styleManager: StyleManager) {}
+
+  clear(): void {
+    this.styleManager.clear();
+  }
 
   updateAndRefreshCssClassesOfCell(bpmnElementId: string, cssClasses: string[]): void {
     this.updateAndRefreshCssClassesOfElement(bpmnElementId, cssClasses);
@@ -54,9 +58,9 @@ export default class GraphCellUpdater {
       return;
     }
 
-    let cellStyle = cell.getStyle();
-    this.styleManager.storeStyleIfIsNotStored(cell, cellStyle);
+    this.styleManager.ensureStyleIsStored(cell);
 
+    let cellStyle = cell.getStyle();
     cellStyle = setStyle(cellStyle, BpmnStyleIdentifier.EXTRA_CSS_CLASSES, cssClasses.join(','));
     model.setStyle(cell, cellStyle);
   }
@@ -98,9 +102,9 @@ export default class GraphCellUpdater {
 
     this.graph.batchUpdate(() => {
       for (const cell of cells) {
-        let cellStyle = cell.getStyle();
-        this.styleManager.storeStyleIfIsNotStored(cell, cellStyle);
+        this.styleManager.ensureStyleIsStored(cell);
 
+        let cellStyle = cell.getStyle();
         cellStyle = setStyle(cellStyle, mxgraph.mxConstants.STYLE_OPACITY, styleUpdate.opacity, ensureOpacityValue);
         cellStyle = updateStroke(cellStyle, styleUpdate.stroke);
         cellStyle = updateFont(cellStyle, styleUpdate.font);
@@ -115,12 +119,13 @@ export default class GraphCellUpdater {
   }
 
   resetStyle(bpmnElementIds: string[]): void {
-    const model = this.graph.getModel();
-
     this.graph.batchUpdate(() => {
-      const cells = bpmnElementIds.length == 0 ? model.getDescendants(this.graph.getDefaultParent()) : bpmnElementIds.map(id => model.getCell(id));
-      for (const cell of cells) {
-        this.styleManager.resetStyle(cell);
+      if (bpmnElementIds.length == 0) {
+        this.styleManager.resetAllStyles();
+      } else {
+        for (const id of bpmnElementIds) {
+          this.styleManager.resetStyleIfIsStored(id);
+        }
       }
     });
   }
diff --git a/src/component/mxgraph/style/StyleManager.ts b/src/component/mxgraph/style/StyleManager.ts
index beb7e5fb32..42d342d6e5 100644
--- a/src/component/mxgraph/style/StyleManager.ts
+++ b/src/component/mxgraph/style/StyleManager.ts
@@ -19,51 +19,47 @@ import { setStyle } from './utils';
 import type { CssRegistry } from '../../registry/css-registry';
 
 export class StyleManager {
-  /**
-   * Contains the style of each cell.
-   */
-  private stylesByCell: Map<mxCell, string> = new Map();
+  private stylesCache: Map<string, string> = new Map();
 
-  /**
-   * Creates a new instance of the StyleManager.
-   *
-   * @param cssRegistry The CSS registry to get class names from.
-   * @param model The mxGraphModel instance.
-   */
   constructor(readonly cssRegistry: CssRegistry, readonly model: mxGraphModel) {}
 
-  /**
-   * Deletes all saved styles.
-   */
   clear(): void {
-    this.stylesByCell.clear();
+    this.stylesCache.clear();
+  }
+
+  resetAllStyles(): void {
+    for (const cellId of this.stylesCache.keys()) {
+      const style = this.stylesCache.get(cellId);
+      this.resetStyle(cellId, style);
+    }
   }
 
   /**
-   * Resets the style of a cell and applies the CSS classes.
+   * Resets the style of a cell and applies its CSS classes.
    *
-   * @param cell The mxCell whose style is to be reset.
+   * @param cellId The ID of the mxCell whose style is to be reset.
    */
-  resetStyle(cell: mxCell): void {
-    if (this.stylesByCell.get(cell)) {
-      const cssClasses = this.cssRegistry.getClassNames(cell.getId());
+  resetStyleIfIsStored(cellId: string): void {
+    const style = this.stylesCache.get(cellId);
+    if (style) {
+      this.resetStyle(cellId, style);
+    }
+  }
 
-      const style = setStyle(this.stylesByCell.get(cell), BpmnStyleIdentifier.EXTRA_CSS_CLASSES, cssClasses.join(','));
-      this.model.setStyle(cell, style);
+  private resetStyle(cellId: string, style: string): void {
+    const cell = this.model.getCell(cellId);
+    const cssClasses = this.cssRegistry.getClassNames(cellId);
 
-      this.stylesByCell.delete(cell);
-    }
+    const styleWithCssClasses = setStyle(style, BpmnStyleIdentifier.EXTRA_CSS_CLASSES, cssClasses.join(','));
+    this.model.setStyle(cell, styleWithCssClasses);
+
+    this.stylesCache.delete(cellId);
   }
 
-  /**
-   * Stores the style for a cell if it is not already stored.
-   *
-   * @param cell The mxCell for which the style is to be stored.
-   * @param style The style to store.
-   */
-  storeStyleIfIsNotStored(cell: mxCell, style: string): void {
-    if (!this.stylesByCell.get(cell)) {
-      this.stylesByCell.set(cell, style);
+  ensureStyleIsStored(cell: mxCell): void {
+    const cellId = cell.getId();
+    if (!this.stylesCache.get(cellId)) {
+      this.stylesCache.set(cellId, cell.getStyle());
     }
   }
 }
diff --git a/src/component/registry/bpmn-elements-registry.ts b/src/component/registry/bpmn-elements-registry.ts
index e955ff2fe9..943b40b7fa 100644
--- a/src/component/registry/bpmn-elements-registry.ts
+++ b/src/component/registry/bpmn-elements-registry.ts
@@ -64,7 +64,7 @@ export class BpmnElementsRegistry {
   ) {
     this.bpmnModelRegistry.registerOnLoadCallback(() => {
       this.cssRegistry.clear();
-      this.graphCellUpdater.styleManager.clear();
+      this.graphCellUpdater.clear();
     });
   }