diff --git a/Build/Sources/TypeScript/backend/Resources/Public/TypeScript/Module/Router.ts b/Build/Sources/TypeScript/backend/Resources/Public/TypeScript/Module/Router.ts
index bab606b2726763fdac8f9935d95134693eff93da..a82025448d83e8aef218cf963b440f23ae1fd9e7 100644
--- a/Build/Sources/TypeScript/backend/Resources/Public/TypeScript/Module/Router.ts
+++ b/Build/Sources/TypeScript/backend/Resources/Public/TypeScript/Module/Router.ts
@@ -170,7 +170,14 @@ export class ModuleRouter extends LitElement {
 
     try {
       const module = await import(moduleName);
-      // @todo: Check if .componentName exists
+      element = this.querySelector(`*[slot="${moduleName}"]`);
+      if (element !== null) {
+        // The element has been created parallelly during the asynchronous module load; use that instance
+        return element;
+      }
+      if (!('componentName' in module)) {
+        throw new Error(`module ${moduleName} is missing the "componentName" export`);
+      }
       element = document.createElement(module.componentName);
     } catch (e) {
       console.error({msg: `Error importing ${moduleName} as backend module`, err: e})
diff --git a/typo3/sysext/backend/Resources/Public/JavaScript/Module/Router.js b/typo3/sysext/backend/Resources/Public/JavaScript/Module/Router.js
index d55f91f3f149255af33bfad41e9b8a9bec5d5298..47789e2ca933d8efcd70345db821d55226da135b 100644
--- a/typo3/sysext/backend/Resources/Public/JavaScript/Module/Router.js
+++ b/typo3/sysext/backend/Resources/Public/JavaScript/Module/Router.js
@@ -10,7 +10,7 @@
  *
  * The TYPO3 project - inspiring people to share!
  */
-var __createBinding=this&&this.__createBinding||(Object.create?function(t,e,o,r){void 0===r&&(r=o);var i=Object.getOwnPropertyDescriptor(e,o);i&&!("get"in i?!e.__esModule:i.writable||i.configurable)||(i={enumerable:!0,get:function(){return e[o]}}),Object.defineProperty(t,r,i)}:function(t,e,o,r){void 0===r&&(r=o),t[r]=e[o]}),__setModuleDefault=this&&this.__setModuleDefault||(Object.create?function(t,e){Object.defineProperty(t,"default",{enumerable:!0,value:e})}:function(t,e){t.default=e}),__decorate=this&&this.__decorate||function(t,e,o,r){var i,n=arguments.length,l=n<3?e:null===r?r=Object.getOwnPropertyDescriptor(e,o):r;if("object"==typeof Reflect&&"function"==typeof Reflect.decorate)l=Reflect.decorate(t,e,o,r);else for(var a=t.length-1;a>=0;a--)(i=t[a])&&(l=(n<3?i(l):n>3?i(e,o,l):i(e,o))||l);return n>3&&l&&Object.defineProperty(e,o,l),l},__importStar=this&&this.__importStar||function(t){if(t&&t.__esModule)return t;var e={};if(null!=t)for(var o in t)"default"!==o&&Object.prototype.hasOwnProperty.call(t,o)&&__createBinding(e,t,o);return __setModuleDefault(e,t),e};define(["require","exports","lit","lit/decorators","../Module"],(function(t,e,o,r,i){"use strict";Object.defineProperty(e,"__esModule",{value:!0}),e.ModuleRouter=void 0;const n="TYPO3/CMS/Backend/Module/Iframe",l=(t,e)=>!0;let a=class extends o.LitElement{constructor(){super(),this.module="",this.endpoint="",this.addEventListener("typo3-module-load",({target:t,detail:e})=>{const o=t.getAttribute("slot");this.pushState({slotName:o,detail:e})}),this.addEventListener("typo3-module-loaded",({detail:t})=>{this.updateBrowserState(t)}),this.addEventListener("typo3-iframe-load",({detail:t})=>{let e={slotName:n,detail:t};if(e.detail.url.includes(this.stateTrackerUrl+"?state=")){const t=e.detail.url.split("?state=");e=JSON.parse(decodeURIComponent(t[1]||"{}"))}this.slotElement.getAttribute("name")!==e.slotName&&this.slotElement.setAttribute("name",e.slotName),this.markActive(e.slotName,this.slotElement.getAttribute("name")===n?null:e.detail.url,!1),this.updateBrowserState(e.detail),this.parentElement.dispatchEvent(new CustomEvent("typo3-module-load",{bubbles:!0,composed:!0,detail:e.detail}))}),this.addEventListener("typo3-iframe-loaded",({detail:t})=>{this.updateBrowserState(t),this.parentElement.dispatchEvent(new CustomEvent("typo3-module-loaded",{bubbles:!0,composed:!0,detail:t}))})}render(){const t=(0,i.getRecordFromName)(this.module).component||n;return o.html`<slot name="${t}"></slot>`}updated(){const t=(0,i.getRecordFromName)(this.module).component||n;this.markActive(t,this.endpoint)}async markActive(t,e,o=!0){const r=await this.getModuleElement(t);e&&(o||r.getAttribute("endpoint")!==e)&&r.setAttribute("endpoint",e),r.hasAttribute("active")||r.setAttribute("active","");for(let t=r.previousElementSibling;null!==t;t=t.previousElementSibling)t.removeAttribute("active");for(let t=r.nextElementSibling;null!==t;t=t.nextElementSibling)t.removeAttribute("active")}async getModuleElement(e){let o=this.querySelector(`*[slot="${e}"]`);if(null!==o)return o;try{const r=await new Promise((o,r)=>{t([e],o,r)}).then(__importStar);o=document.createElement(r.componentName)}catch(t){throw console.error({msg:`Error importing ${e} as backend module`,err:t}),t}return o.setAttribute("slot",e),this.appendChild(o),o}async pushState(t){const e=this.stateTrackerUrl+"?state="+encodeURIComponent(JSON.stringify(t));(await this.getModuleElement(n)).setAttribute("endpoint",e)}updateBrowserState(t){const e=new URL(t.url||"",window.location.origin),o=new URLSearchParams(e.search),r="title"in t?t.title:"";if(null!==r){const t=[this.sitename];""!==r&&t.unshift(r),this.sitenameFirst&&t.reverse(),document.title=t.join(" · ")}if(!o.has("token")){if(!o.has("install[controller]"))return;{const t=o.get("install[controller]");o.delete("install[controller]"),o.delete("install[context]"),e.pathname=e.pathname.replace("/typo3/install.php","/typo3/module/tools/"+t)}}o.delete("token"),e.search=o.toString();const i=e.toString();window.history.replaceState(t,"",i)}};a.styles=o.css`
+var __createBinding=this&&this.__createBinding||(Object.create?function(t,e,o,r){void 0===r&&(r=o);var i=Object.getOwnPropertyDescriptor(e,o);i&&!("get"in i?!e.__esModule:i.writable||i.configurable)||(i={enumerable:!0,get:function(){return e[o]}}),Object.defineProperty(t,r,i)}:function(t,e,o,r){void 0===r&&(r=o),t[r]=e[o]}),__setModuleDefault=this&&this.__setModuleDefault||(Object.create?function(t,e){Object.defineProperty(t,"default",{enumerable:!0,value:e})}:function(t,e){t.default=e}),__decorate=this&&this.__decorate||function(t,e,o,r){var i,n=arguments.length,l=n<3?e:null===r?r=Object.getOwnPropertyDescriptor(e,o):r;if("object"==typeof Reflect&&"function"==typeof Reflect.decorate)l=Reflect.decorate(t,e,o,r);else for(var a=t.length-1;a>=0;a--)(i=t[a])&&(l=(n<3?i(l):n>3?i(e,o,l):i(e,o))||l);return n>3&&l&&Object.defineProperty(e,o,l),l},__importStar=this&&this.__importStar||function(t){if(t&&t.__esModule)return t;var e={};if(null!=t)for(var o in t)"default"!==o&&Object.prototype.hasOwnProperty.call(t,o)&&__createBinding(e,t,o);return __setModuleDefault(e,t),e};define(["require","exports","lit","lit/decorators","../Module"],(function(t,e,o,r,i){"use strict";Object.defineProperty(e,"__esModule",{value:!0}),e.ModuleRouter=void 0;const n="TYPO3/CMS/Backend/Module/Iframe",l=(t,e)=>!0;let a=class extends o.LitElement{constructor(){super(),this.module="",this.endpoint="",this.addEventListener("typo3-module-load",({target:t,detail:e})=>{const o=t.getAttribute("slot");this.pushState({slotName:o,detail:e})}),this.addEventListener("typo3-module-loaded",({detail:t})=>{this.updateBrowserState(t)}),this.addEventListener("typo3-iframe-load",({detail:t})=>{let e={slotName:n,detail:t};if(e.detail.url.includes(this.stateTrackerUrl+"?state=")){const t=e.detail.url.split("?state=");e=JSON.parse(decodeURIComponent(t[1]||"{}"))}this.slotElement.getAttribute("name")!==e.slotName&&this.slotElement.setAttribute("name",e.slotName),this.markActive(e.slotName,this.slotElement.getAttribute("name")===n?null:e.detail.url,!1),this.updateBrowserState(e.detail),this.parentElement.dispatchEvent(new CustomEvent("typo3-module-load",{bubbles:!0,composed:!0,detail:e.detail}))}),this.addEventListener("typo3-iframe-loaded",({detail:t})=>{this.updateBrowserState(t),this.parentElement.dispatchEvent(new CustomEvent("typo3-module-loaded",{bubbles:!0,composed:!0,detail:t}))})}render(){const t=(0,i.getRecordFromName)(this.module).component||n;return o.html`<slot name="${t}"></slot>`}updated(){const t=(0,i.getRecordFromName)(this.module).component||n;this.markActive(t,this.endpoint)}async markActive(t,e,o=!0){const r=await this.getModuleElement(t);e&&(o||r.getAttribute("endpoint")!==e)&&r.setAttribute("endpoint",e),r.hasAttribute("active")||r.setAttribute("active","");for(let t=r.previousElementSibling;null!==t;t=t.previousElementSibling)t.removeAttribute("active");for(let t=r.nextElementSibling;null!==t;t=t.nextElementSibling)t.removeAttribute("active")}async getModuleElement(e){let o=this.querySelector(`*[slot="${e}"]`);if(null!==o)return o;try{const r=await new Promise((o,r)=>{t([e],o,r)}).then(__importStar);if(o=this.querySelector(`*[slot="${e}"]`),null!==o)return o;if(!("componentName"in r))throw new Error(`module ${e} is missing the "componentName" export`);o=document.createElement(r.componentName)}catch(t){throw console.error({msg:`Error importing ${e} as backend module`,err:t}),t}return o.setAttribute("slot",e),this.appendChild(o),o}async pushState(t){const e=this.stateTrackerUrl+"?state="+encodeURIComponent(JSON.stringify(t));(await this.getModuleElement(n)).setAttribute("endpoint",e)}updateBrowserState(t){const e=new URL(t.url||"",window.location.origin),o=new URLSearchParams(e.search),r="title"in t?t.title:"";if(null!==r){const t=[this.sitename];""!==r&&t.unshift(r),this.sitenameFirst&&t.reverse(),document.title=t.join(" · ")}if(!o.has("token")){if(!o.has("install[controller]"))return;{const t=o.get("install[controller]");o.delete("install[controller]"),o.delete("install[context]"),e.pathname=e.pathname.replace("/typo3/install.php","/typo3/module/tools/"+t)}}o.delete("token"),e.search=o.toString();const i=e.toString();window.history.replaceState(t,"",i)}};a.styles=o.css`
     :host {
       width: 100%;
       min-height: 100%;