Switch to el.content.childNodes.length

src/utils.js

@@ -23,7 +23,7 @@ export function isTesting() {
 export function warnIfMalformedTemplate(el, directive) {
     if (el.tagName.toLowerCase() !== 'template') {
         console.warn(`Alpine: [${directive}] directive should only be added to <template> tags. See https://github.com/alpinejs/alpine#${directive}`)
-    } else if (el.content.childElementCount !== 1) {
+    } else if (el.content.childNodes.length !== 1) {
         console.warn(`Alpine: <template> tag with [${directive}] encountered with multiple element roots. Make sure <template> only has a single child node.`)
     }
 }