diff --git a/src/client/updaters/updateTags.js b/src/client/updaters/updateTags.js
index b93a971..9f9ddad 100644
--- a/src/client/updaters/updateTags.js
+++ b/src/client/updaters/updateTags.js
@@ -47,7 +47,7 @@ export default function _updateTags (options = {}) {
               } else {
                 newElement.appendChild(document.createTextNode(tag.cssText))
               }
-            } else if ([options.tagIDKeyName, 'body'].includes(attr)) {
+            } else if ([options.tagIDKeyName, 'body'].indexOf(attr) !== -1) {
               const _attr = `data-${attr}`
               const value = (typeof tag[attr] === 'undefined') ? '' : tag[attr]
               newElement.setAttribute(_attr, value)
diff --git a/src/server/generators/tagGenerator.js b/src/server/generators/tagGenerator.js
index 30fc057..426a563 100644
--- a/src/server/generators/tagGenerator.js
+++ b/src/server/generators/tagGenerator.js
@@ -24,7 +24,7 @@ export default function _tagGenerator (options = {}) {
                 return attrsStr
               // these form the attribute list for this tag
               default:
-                if ([options.tagIDKeyName, 'body'].includes(attr)) {
+                if ([options.tagIDKeyName, 'body'].indexOf(attr) !== -1) {
                   return `${attrsStr} data-${attr}="${tag[attr]}"`
                 }
                 return typeof tag[attr] === 'undefined'