#3518708 Fix for inline vh units causing iframe to grow infinitely

Fix for inline vh units of elements in the preview to be converted to static height based on height of iframe

Closes #3518708

ui/src/hooks/useSyncIframeHeightToContent.ts

@@ -62,10 +62,7 @@ function useSyncIframeHeightToContent(
           const elements: NodeListOf<HTMLElement> =
             iframeHTML.querySelectorAll('*');
           elements.forEach((element) => {
-            if (
-              element instanceof HTMLElement &&
-              element.style.height.endsWith('vh')
-            ) {
+            if (element.style.height.endsWith('vh')) {
               const vhValue = parseFloat(element.style.height);
               const newHeight = (vhValue / 100) * height;
               element.style.maxHeight = newHeight + 'px';