diff --git a/package.json b/package.json
index 2d901e8..b391df4 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@vaadin-component-factory/vcf-anchor-nav",
-  "version": "3.0.0",
+  "version": "3.0.1",
   "description": "Component with tabs used as anchor navigation and content sections. Automates the linking of tabs and sections.",
   "main": "vcf-anchor-nav.js",
   "author": "Vaadin Ltd",
diff --git a/src/vcf-anchor-nav-section.js b/src/vcf-anchor-nav-section.js
index deb84b7..4961946 100644
--- a/src/vcf-anchor-nav-section.js
+++ b/src/vcf-anchor-nav-section.js
@@ -53,7 +53,6 @@ class AnchorNavSectionElement extends ElementMixin(ThemableMixin(PolymerElement)
           border-bottom: var(--anchor-nav-section-border-width) solid var(--anchor-nav-section-border-color);
         }
 
-        #defaultHeader,
         ::slotted([slot='header']) {
           margin: 0;
           padding: var(--lumo-space-m);
@@ -115,8 +114,8 @@ class AnchorNavSectionElement extends ElementMixin(ThemableMixin(PolymerElement)
   }
 
   _createHeader() {
-    const customHeader = this.querySelector('h2');
-    if (customHeader && customHeader.assignedSlot && customHeader.assignedSlot.name == 'header') {
+    const customHeader = this.querySelector('[slot="header"]');
+    if (customHeader) {
       customHeader.setAttribute('id', this.headerId);
     } else {
       const header = document.createElement('h2');