Table headers do not stick to the top when scrolling in Firefox

Issue Summary

1. For long tables in Confluence, as you scroll down the page, the header would stick to the top so that it appears even when we're viewing lower entries in the table.
2. In Firefox however, this functionality seems to break intermittently.

Expected Results

1. Header appears even after scrolling down.
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Actual Results

1. In Firefox, header does not appear from time to time.
2. This behavior is not seen in Google Chrome
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Steps to Reproduce

1. Create table with header and lots of rows.
2. Scroll down.
   • As issue is intermittent, if issue not reproducible, refresh the page and scroll again.

     Workaround

• Currently there is no known workaround for this behavior. A workaround will be added here when available