diff --git a/src/dbp-official-signature-pdf-upload.js b/src/dbp-official-signature-pdf-upload.js
index 8789056b5c4229c4bcdce2d25893fc2d7792a46f..c1f2ffff49399cce1b6cede6c3112b4e54107cb3 100644
--- a/src/dbp-official-signature-pdf-upload.js
+++ b/src/dbp-official-signature-pdf-upload.js
@@ -64,7 +64,8 @@ class OfficialSignaturePdfUpload extends ScopedElementsMixin(DBPSignatureLitElem
     }
 
     static get properties() {
-        return this.getProperties({
+        return {
+            ...super.properties,
             lang: { type: String },
             entryPointUrl: { type: String, attribute: 'entry-point-url' },
             nextcloudWebAppPasswordURL: { type: String, attribute: 'nextcloud-web-app-password-url' },
@@ -88,7 +89,7 @@ class OfficialSignaturePdfUpload extends ScopedElementsMixin(DBPSignatureLitElem
             signaturePlacementInProgress: { type: Boolean, attribute: false },
             withSigBlock: { type: Boolean, attribute: false },
             isSignaturePlacement: { type: Boolean, attribute: false },
-        });
+        };
     }
 
     connectedCallback() {
diff --git a/src/dbp-pdf-preview.js b/src/dbp-pdf-preview.js
index 63a8dc7570f806c38dbf5b095d687b94bb20b2a1..94e82d0bd9433f4e06da97999dde89f9d6d7cda8 100644
--- a/src/dbp-pdf-preview.js
+++ b/src/dbp-pdf-preview.js
@@ -51,7 +51,8 @@ export class PdfPreview extends ScopedElementsMixin(DBPLitElement) {
      * See: https://lit-element.polymer-project.org/guide/properties#initialize
      */
     static get properties() {
-        return this.getProperties({
+        return {
+            ...super.properties,
             lang: { type: String },
             currentPage: { type: Number, attribute: false },
             totalPages: { type: Number, attribute: false },
@@ -63,7 +64,7 @@ export class PdfPreview extends ScopedElementsMixin(DBPLitElement) {
             signature_width: { type: Number, attribute: 'signature-width' },
             signature_height: { type: Number, attribute: 'signature-height' },
             allowSignatureRotation: { type: Boolean, attribute: 'allow-signature-rotation' },
-        });
+        };
     }
 
     update(changedProperties) {
diff --git a/src/dbp-qualified-signature-pdf-upload.js b/src/dbp-qualified-signature-pdf-upload.js
index c810b89aac0a282dcaa308b1846d05dbc3c17b5b..6b39cc43f7f037cec9d5f9d47e7fd8c92994e3fe 100644
--- a/src/dbp-qualified-signature-pdf-upload.js
+++ b/src/dbp-qualified-signature-pdf-upload.js
@@ -66,7 +66,8 @@ class QualifiedSignaturePdfUpload extends ScopedElementsMixin(DBPSignatureLitEle
     }
 
     static get properties() {
-        return this.getProperties({
+        return {
+            ...super.properties,
             lang: { type: String },
             entryPointUrl: { type: String, attribute: 'entry-point-url' },
             nextcloudWebAppPasswordURL: { type: String, attribute: 'nextcloud-web-app-password-url' },
@@ -91,7 +92,7 @@ class QualifiedSignaturePdfUpload extends ScopedElementsMixin(DBPSignatureLitEle
             signaturePlacementInProgress: { type: Boolean, attribute: false },
             withSigBlock: { type: Boolean, attribute: false },
             isSignaturePlacement: { type: Boolean, attribute: false },
-        });
+        };
     }
 
     connectedCallback() {
diff --git a/src/dbp-signature-lit-element.js b/src/dbp-signature-lit-element.js
index 6f286f68d0a1538eee22025fbc92ce5b906d5269..c9882105ebbee719bd745ab08f21f4f9e4260f1f 100644
--- a/src/dbp-signature-lit-element.js
+++ b/src/dbp-signature-lit-element.js
@@ -70,9 +70,10 @@ export default class DBPSignatureLitElement extends DBPSignatureBaseLitElement {
     }
 
     static get properties() {
-        return this.getProperties({
+        return {
+            ...super.properties,
             showNextcloudFilePicker: { type: Boolean, attribute: 'show-nextcloud-file-picker' },
-        });
+        };
     }
 
     /**
diff --git a/src/dbp-signature-verification-full.js b/src/dbp-signature-verification-full.js
index 204115354d8ed5d3a6908386fe44ca3b84ee737c..05f475941b6203f106ab45044c46b95b3d19a0d4 100644
--- a/src/dbp-signature-verification-full.js
+++ b/src/dbp-signature-verification-full.js
@@ -53,7 +53,8 @@ class SignatureVerificationFull extends ScopedElementsMixin(DBPSignatureLitEleme
     }
 
     static get properties() {
-        return this.getProperties({
+        return {
+            ...super.properties,
             lang: { type: String },
             entryPointUrl: { type: String, attribute: 'entry-point-url' },
             nextcloudWebAppPasswordURL: { type: String, attribute: 'nextcloud-web-app-password-url' },
@@ -75,7 +76,7 @@ class SignatureVerificationFull extends ScopedElementsMixin(DBPSignatureLitEleme
             currentFileName: { type: String, attribute: false },
             previewInProgress: { type: Boolean, attribute: false },
             isSignaturePlacement: { type: Boolean, attribute: false },
-        });
+        };
     }
 
     connectedCallback() {
diff --git a/src/dbp-signature-verification.js b/src/dbp-signature-verification.js
index 9996ac95e50643d0fc721d360d68fe3364cc6549..e78507cd2e0a8d148a533e172de6a680c584a7da 100644
--- a/src/dbp-signature-verification.js
+++ b/src/dbp-signature-verification.js
@@ -18,9 +18,10 @@ class SignatureVerification extends ScopedElementsMixin(DBPSignatureLitElement)
     }
 
     static get properties() {
-        return this.getProperties({
+        return {
+            ...super.properties,
             lang: { type: String },
-        });
+        };
     }
 
     update(changedProperties) {