The following publicly cacheable, compressible resources should have a "Vary: Accept-Encoding" header:

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#1

Hi I´m tetsing my Blog speed with https://tools.pingdom.com and I see this error please can you help me to resolve it.

The following publicly cacheable, compressible resources should have a “Vary: Accept-Encoding” header:

http://hwstechc.wwwls29.a2hosted.com/wp-content/themes/pro-child/style.css?ver=1.1.1

#2

Hello There,

Thanks for writing in! Please ignore any of these errors at the moment. Your grade is A (94) and this is good. I would highly recommend that you moved your site to your production domain name (http://example.com) first and then do the test again. If any of the errors exist, then this is the time that we will figure out how to resolve it.

Perhaps, this article could help you: https://kinsta.com/knowledgebase/specify-vary-accept-encoding-header/

Best Regards.