diff --git a/src/app/shared/form/vocabulary-treeview/vocabulary-treeview.component.html b/src/app/shared/form/vocabulary-treeview/vocabulary-treeview.component.html
index 64442b258d..3b858faac4 100644
--- a/src/app/shared/form/vocabulary-treeview/vocabulary-treeview.component.html
+++ b/src/app/shared/form/vocabulary-treeview/vocabulary-treeview.component.html
@@ -23,7 +23,7 @@
     <!-- Leaf node -->
     <cdk-tree-node *cdkTreeNodeDef="let node" cdkTreeNodePadding class="d-flex">
         <button type="button" class="btn btn-default" cdkTreeNodeToggle>
-          <span class="fas fa-angle-right invisible" aria-hidden="true"></span>
+          <span class="fas fa-fw fa-angle-right invisible" aria-hidden="true"></span>
         </button>
           <label *ngIf="multiSelect" class="d-flex align-items-center m-0 p-0 form-check"
                  [class.text-success]="node.isSelected"
@@ -55,7 +55,7 @@
         <button type="button" class="btn btn-default" cdkTreeNodeToggle
                 [attr.aria-label]="'toggle ' + node.name"
                 (click)="loadChildren(node)">
-          <span class="fas {{treeControl.isExpanded(node) ? 'fa-angle-down' : 'fa-angle-right'}}"
+          <span class="fas fa-fw {{treeControl.isExpanded(node) ? 'fa-angle-down' : 'fa-angle-right'}}"
                 aria-hidden="true"></span>
         </button>