[Hummingbird] Performance test suggests using font-display: swap

On one of the sites I’m building Hummingbird suggested adding font-display: swap for custom fonts I’m using, but I wasn’t able to make it work there even after adding the CSS code.

Also, I’ve set browser caching to be 8 days and Hummingbirds shows that in the back-end, but the test shows that assets have different values set, like 3h etc.

Can you assist?