diff --git a/src/types/YMap.js b/src/types/YMap.js
index c640ae54..e2dd7a49 100644
--- a/src/types/YMap.js
+++ b/src/types/YMap.js
@@ -206,9 +206,11 @@ export class YMap extends AbstractType {
 
   /**
    * Adds or updates an element with a specified key and value.
+   * @template {MapType} VAL
    *
    * @param {string} key The key of the element to add to this YMap
-   * @param {MapType} value The value of the element to add
+   * @param {VAL} value The value of the element to add
+   * @return {VAL}
    */
   set (key, value) {
     if (this.doc !== null) {
diff --git a/src/types/YXmlElement.js b/src/types/YXmlElement.js
index 905ad2a3..92088cdd 100644
--- a/src/types/YXmlElement.js
+++ b/src/types/YXmlElement.js
@@ -1,3 +1,4 @@
+import * as object from 'lib0/object'
 
 import {
   YXmlFragment,
@@ -12,6 +13,10 @@ import {
   YXmlText, ContentType, AbstractType, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Doc, Item // eslint-disable-line
 } from '../internals.js'
 
+/**
+ * @typedef {Object|number|null|Array<any>|string|Uint8Array|AbstractType<any>} ValueTypes
+ */
+
 /**
  * An YXmlElement imitates the behavior of a
  * {@link https://developer.mozilla.org/en-US/docs/Web/API/Element|Dom Element}.
@@ -19,7 +24,7 @@ import {
  * * An YXmlElement has attributes (key value pairs)
  * * An YXmlElement has childElements that must inherit from YXmlElement
  *
- * @template {{ [key: string]: Object|number|null|Array<any>|string|Uint8Array|AbstractType<any> }} [KV={ [key: string]: string }]
+ * @template {{ [key: string]: ValueTypes }} [KV={ [key: string]: string }]
  */
 export class YXmlElement extends YXmlFragment {
   constructor (nodeName = 'UNDEFINED') {
@@ -75,14 +80,19 @@ export class YXmlElement extends YXmlFragment {
   }
 
   /**
-   * @return {YXmlElement}
+   * @return {YXmlElement<KV>}
    */
   clone () {
+    /**
+     * @type {YXmlElement<KV>}
+     */
     const el = new YXmlElement(this.nodeName)
     const attrs = this.getAttributes()
-    for (const key in attrs) {
-      el.setAttribute(key, attrs[key])
-    }
+    object.forEach(attrs, (value, key) => {
+      if (typeof value === 'string') {
+        el.setAttribute(key, value)
+      }
+    })
     // @ts-ignore
     el.insert(0, this.toArray().map(item => item instanceof AbstractType ? item.clone() : item))
     return el
@@ -182,12 +192,12 @@ export class YXmlElement extends YXmlFragment {
   /**
    * Returns all attribute name/value pairs in a JSON Object.
    *
-   * @return {Object<string, any>} A JSON Object that describes the attributes.
+   * @return {{ [Key in Extract<keyof KV,string>]?: KV[Key]}} A JSON Object that describes the attributes.
    *
    * @public
    */
   getAttributes () {
-    return typeMapGetAll(this)
+    return /** @type {any} */ (typeMapGetAll(this))
   }
 
   /**
@@ -209,7 +219,10 @@ export class YXmlElement extends YXmlFragment {
     const dom = _document.createElement(this.nodeName)
     const attrs = this.getAttributes()
     for (const key in attrs) {
-      dom.setAttribute(key, attrs[key])
+      const value = attrs[key]
+      if (typeof value === 'string') {
+        dom.setAttribute(key, value)
+      }
     }
     typeListForEach(this, yxml => {
       dom.appendChild(yxml.toDOM(_document, hooks, binding))
diff --git a/tests/y-xml.tests.js b/tests/y-xml.tests.js
index 619d9ee9..1ae2c813 100644
--- a/tests/y-xml.tests.js
+++ b/tests/y-xml.tests.js
@@ -3,6 +3,33 @@ import * as Y from '../src/index.js'
 
 import * as t from 'lib0/testing'
 
+export const testCustomTypings = () => {
+  const ydoc = new Y.Doc()
+  const ymap = ydoc.getMap()
+  /**
+   * @type {Y.XmlElement<{ num: number, str: string, [k:string]: object|number|string }>}
+   */
+  const yxml = ymap.set('yxml', new Y.XmlElement('test'))
+  /**
+   * @type {number|undefined}
+   */
+  const num = yxml.getAttribute('num')
+  /**
+   * @type {string|undefined}
+   */
+  const str = yxml.getAttribute('str')
+  /**
+   * @type {object|number|string|undefined}
+   */
+  const dtrn = yxml.getAttribute('dtrn')
+  const attrs = yxml.getAttributes()
+  /**
+   * @type {object|number|string|undefined}
+   */
+  const any = attrs.shouldBeAny
+  console.log({ num, str, dtrn, attrs, any })
+}
+
 /**
  * @param {t.TestCase} tc
  */
@@ -92,9 +119,9 @@ export const testTreewalker = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testYtextAttributes = tc => {
+export const testYtextAttributes = _tc => {
   const ydoc = new Y.Doc()
   const ytext = /** @type {Y.XmlText} */ (ydoc.get('', Y.XmlText))
   ytext.observe(event => {
@@ -106,9 +133,9 @@ export const testYtextAttributes = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testSiblings = tc => {
+export const testSiblings = _tc => {
   const ydoc = new Y.Doc()
   const yxml = ydoc.getXmlFragment()
   const first = new Y.XmlText()
@@ -122,9 +149,9 @@ export const testSiblings = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testInsertafter = tc => {
+export const testInsertafter = _tc => {
   const ydoc = new Y.Doc()
   const yxml = ydoc.getXmlFragment()
   const first = new Y.XmlText()
@@ -152,9 +179,9 @@ export const testInsertafter = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testClone = tc => {
+export const testClone = _tc => {
   const ydoc = new Y.Doc()
   const yxml = ydoc.getXmlFragment()
   const first = new Y.XmlText('text')
@@ -170,9 +197,9 @@ export const testClone = tc => {
 }
 
 /**
- * @param {t.TestCase} tc
+ * @param {t.TestCase} _tc
  */
-export const testFormattingBug = tc => {
+export const testFormattingBug = _tc => {
   const ydoc = new Y.Doc()
   const yxml = /** @type {Y.XmlText} */ (ydoc.get('', Y.XmlText))
   const delta = [