From d7f81a64f8f73d0ea3e85a2779d733b009c63fd8 Mon Sep 17 00:00:00 2001
From: Sebastiaan Dammann <sebastiaandammann@outlook.com>
Date: Thu, 1 Feb 2018 18:50:31 +0100
Subject: [PATCH] Found workaround for Microsoft/TypeScript/issues/21517 until
 it is fixed

---
 src/App/js/AppFramework/Forms/ValidationMessage.ts | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/App/js/AppFramework/Forms/ValidationMessage.ts b/src/App/js/AppFramework/Forms/ValidationMessage.ts
index 1364334b..3cf950d7 100644
--- a/src/App/js/AppFramework/Forms/ValidationMessage.ts
+++ b/src/App/js/AppFramework/Forms/ValidationMessage.ts
@@ -71,10 +71,11 @@ ko.bindingHandlers.validationProperty = {
                     element.setAttribute('required', 'required');
                 }
             } else {
+                const workaround = element as HTMLInputElement;
                 if (validationState) {
-                    element.classList.add('is-invalid');
+                    workaround.classList.add('is-invalid');
                 } else {
-                    element.classList.remove('is-invalid');
+                    workaround.classList.remove('is-invalid');
                 }
             }
         }