diff --git a/library/ws-widget/collection/src/lib/_common/content-toc/app-toc-about/app-toc-about.component.ts b/library/ws-widget/collection/src/lib/_common/content-toc/app-toc-about/app-toc-about.component.ts
index 605d36a24..b6181efc0 100644
--- a/library/ws-widget/collection/src/lib/_common/content-toc/app-toc-about/app-toc-about.component.ts
+++ b/library/ws-widget/collection/src/lib/_common/content-toc/app-toc-about/app-toc-about.component.ts
@@ -210,22 +210,22 @@ export class AppTocAboutComponent implements OnInit, OnChanges, AfterViewInit, O
     if (changes.selectedTabValue && changes.selectedTabValue.currentValue === 0) {
       setTimeout(() => {
         if (!this.isMobile) {
-          if (this.summaryElem.nativeElement.offsetHeight > 72) {
+          if (this.summaryElem && this.summaryElem.nativeElement.offsetHeight > 72) {
             this.summary.ellipsis = true
           }
 
-          if (this.descElem.nativeElement.offsetHeight > 72) {
+          if (this.descElem && this.descElem.nativeElement.offsetHeight > 72) {
             this.description.ellipsis = true
           }
           if (this.objectivesElem && this.objectivesElem.nativeElement.offsetHeight > 72) {
             this.objectives.ellipsis = true
           }
         } else {
-          if (this.summaryElem.nativeElement.offsetHeight > 48) {
+          if (this.summaryElem && this.summaryElem.nativeElement.offsetHeight > 48) {
             this.summary.ellipsis = true
           }
 
-          if (this.descElem.nativeElement.offsetHeight > 48) {
+          if (this.descElem && this.descElem.nativeElement.offsetHeight > 48) {
             this.description.ellipsis = true
           }
           if (this.objectivesElem && this.objectivesElem.nativeElement.offsetHeight > 48) {