diff --git a/content/apply.js b/content/apply.js
index f1132746..90208d21 100644
--- a/content/apply.js
+++ b/content/apply.js
@@ -88,9 +88,10 @@ const APPLY = (() => {
     // Since it's easy to spoof the browser version in pre-Quantum FF we're checking
     // for getPreventDefault which got removed in FF59 https://bugzil.la/691151
     const EVENT_NAME = chrome.runtime.id;
-    let ready;
+    const usePageScript = CHROME || IS_OWN_PAGE || Event.prototype.getPreventDefault ?
+      Promise.resolve(false) : injectPageScript();
     return (el, content, disabled) =>
-      checkPageScript().then(ok => {
+      usePageScript.then(ok => {
         if (!ok) {
           el.textContent = content;
           // https://github.com/openstyles/stylus/issues/693
@@ -106,14 +107,6 @@ const APPLY = (() => {
         }
       });
 
-    function checkPageScript() {
-      if (!ready) {
-        ready = CHROME || IS_OWN_PAGE || Event.prototype.getPreventDefault ?
-          Promise.resolve(false) : injectPageScript();
-      }
-      return ready;
-    }
-
     function injectPageScript() {
       const scriptContent = EVENT_NAME => {
         document.currentScript.remove();
@@ -156,7 +149,7 @@ const APPLY = (() => {
       script.onerror = resolveFalse;
       window.addEventListener('error', resolveFalse);
       window.addEventListener(EVENT_NAME, handleInit);
-      (document.head || document.documentElement).appendChild(script);
+      document.documentElement.appendChild(script);
       return promise.then(result => {
         script.remove();
         window.removeEventListener(EVENT_NAME, handleInit);