Issue Summary

Page's toolbar/header appears and disappears immediately after scrolling the page up when there are PDF files at the bottom of the page.

Steps to Reproduce

1. Create a Confluence page
2. Add content to this page
3. At the bottom of the page, add 2 or more PDF files
4. Save the page
5. Go to the bottom of the page and start to scroll up

Expected Results

Page's toolbar appears and doesn't disappear when scrolling up the page.

Actual Results

Page's toolbar/header appears and disappears immediately after scrolling the page up.

Workaround

Remove the PDFs from the bottom of the page.