Reply To: Header sometimes gone

Hi Elise, we tried optimize the site like in the guide link you sent here but the site became slower, I use the File Optimization > Optimize CSS Delivery > Remove Unused CSS, and the only problem i see with that feature is the header missing in shop page and main page, so I can whitelist the .css header files and overcome this issue, because the Remove Unused CSS really does the trick on my site and make it very fast and not hurting the UX.
So Please let me know the Header CSS files so I will whitelist them from this feature.
Waiting for your response,
Best regards.