Save cache on cookie-free domain

Hi there!

I’m working on speeding up my website and wanted to see if its possible to save the cache files on a cookie-free domain. Our GTmetrix report shows a long list of files like https://www.straightdental.com/wp-content/cache/wpfc-minified/8k6m5fqy/9ns4i.css that could be on a cookie-free domain. Is that possible?

Best,
Caspar

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