diff --git a/src/bundle/Resources/public/js/scripts/helpers/dom.helper.js b/src/bundle/Resources/public/js/scripts/helpers/dom.helper.js
deleted file mode 100644
index bd6c35c43f..0000000000
--- a/src/bundle/Resources/public/js/scripts/helpers/dom.helper.js
+++ /dev/null
@@ -1,21 +0,0 @@
-import { escapeHTML } from './text.helper';
-
-const safelySetInnerHTML = (node, text) => {
-    node.innerHTML = escapeHTML(text);
-};
-
-const dangerouslySetInnerHTML = (node, text) => {
-    node.innerHTML = text;
-};
-
-const dangerouslyInsertAdjacentHTML = (node, position, text) => {
-    const escapedText = text;
-
-    node.insertAdjacentHTML(position, escapedText);
-};
-
-const dangerouslyAppend = (node, nodeOrText) => {
-    node.append(nodeOrText);
-};
-
-export { safelySetInnerHTML, dangerouslySetInnerHTML, dangerouslyInsertAdjacentHTML, dangerouslyAppend };
diff --git a/src/bundle/Resources/public/js/scripts/helpers/dom.helper.ts b/src/bundle/Resources/public/js/scripts/helpers/dom.helper.ts
new file mode 100644
index 0000000000..4bc81bf444
--- /dev/null
+++ b/src/bundle/Resources/public/js/scripts/helpers/dom.helper.ts
@@ -0,0 +1,33 @@
+import { escapeHTML } from './text.helper';
+
+const safelySetInnerHTML = (node: HTMLElement, text: string): void => {
+    // eslint-disable-next-line no-param-reassign
+    node.innerHTML = escapeHTML(text);
+};
+
+const dangerouslySetInnerHTML = (node: HTMLElement, text: string): void => {
+    // eslint-disable-next-line no-param-reassign
+    node.innerHTML = text;
+};
+
+const dangerouslyInsertAdjacentHTML = (node: HTMLElement, position: InsertPosition, text: string): void => {
+    const escapedText = text;
+
+    node.insertAdjacentHTML(position, escapedText);
+};
+
+const dangerouslyAppend = (node: HTMLElement, nodeOrText: Node | string): void => {
+    node.append(nodeOrText);
+};
+
+const notNullQuerySelector = function <T extends HTMLElement>(node: HTMLElement | Document, selector: string): T {
+    const selectedNode = node.querySelector<T>(selector);
+
+    if (!selectedNode) {
+        throw new Error(`Element for selector '${selector}' not found!`);
+    }
+
+    return selectedNode;
+};
+
+export { safelySetInnerHTML, dangerouslySetInnerHTML, dangerouslyInsertAdjacentHTML, dangerouslyAppend, notNullQuerySelector };
diff --git a/src/bundle/Resources/public/js/scripts/helpers/text.helper.js b/src/bundle/Resources/public/js/scripts/helpers/text.helper.js
deleted file mode 100644
index ac5f88cc3c..0000000000
--- a/src/bundle/Resources/public/js/scripts/helpers/text.helper.js
+++ /dev/null
@@ -1,24 +0,0 @@
-const { document: doc } = window;
-
-const escapeHTML = (string) => {
-    const stringTempNode = doc.createElement('div');
-
-    stringTempNode.appendChild(doc.createTextNode(string));
-
-    return stringTempNode.innerHTML;
-};
-
-const escapeHTMLAttribute = (string) => {
-    if (string === null) {
-        return '';
-    }
-
-    return String(string)
-        .replace(/&/g, '&amp;')
-        .replace(/</g, '&lt;')
-        .replace(/>/g, '&gt;')
-        .replace(/"/g, '&quot;')
-        .replace(/'/g, '&#039;');
-};
-
-export { escapeHTML, escapeHTMLAttribute };
diff --git a/src/bundle/Resources/public/js/scripts/helpers/text.helper.ts b/src/bundle/Resources/public/js/scripts/helpers/text.helper.ts
new file mode 100644
index 0000000000..994c33b193
--- /dev/null
+++ b/src/bundle/Resources/public/js/scripts/helpers/text.helper.ts
@@ -0,0 +1,20 @@
+const { document: doc } = window;
+
+const escapeHTML = (str: string): string => {
+    const stringTempNode = doc.createElement('div');
+
+    stringTempNode.appendChild(doc.createTextNode(str));
+
+    return stringTempNode.innerHTML;
+};
+
+const escapeHTMLAttribute = (str: unknown): string => {
+    if (str === null || str === undefined) {
+        return '';
+    }
+
+    // eslint-disable-next-line @typescript-eslint/no-base-to-string
+    return String(str).replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;').replace(/'/g, '&#039;');
+};
+
+export { escapeHTML, escapeHTMLAttribute };