diff --git a/Dockerfile b/Dockerfile
index f5ef85b08..8abc7c530 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -47,6 +47,9 @@ RUN ln -s /app/main.js /usr/bin/crawl; ln -s /app/create-login-profile.js /usr/b
 
 WORKDIR /crawls
 
+# enable to test custom behaviors build (from browsertrix-behaviors)
+# COPY behaviors.js /app/node_modules/browsertrix-behaviors/dist/behaviors.js
+
 ADD docker-entrypoint.sh /docker-entrypoint.sh
 ENTRYPOINT ["/docker-entrypoint.sh"]
 
diff --git a/crawler.js b/crawler.js
index af00c31cb..8d747ae1b 100644
--- a/crawler.js
+++ b/crawler.js
@@ -607,11 +607,11 @@ self.__bx_behaviors.selectMainBehavior();
 
     const frameUrl = frame.url();
 
-    const frameElem = await frame.frameElement();
+    // this is all designed to detect and skip PDFs, and other frames that are actually EMBEDs
+    // if there's no tag or an iframe tag, then assume its a regular frame
+    const tagName = await frame.evaluate("window.frameElement && window.frameElement.tagName");
 
-    const tagName = await frame.evaluate(e => e.tagName, frameElem);
-
-    if (tagName !== "IFRAME" && tagName !== "FRAME") {
+    if (tagName && tagName !== "IFRAME" && tagName !== "FRAME") {
       logger.debug("Skipping processing non-frame object", {tagName, frameUrl, ...logDetails}, "behavior");
       return null;
     }