I’ve been running some tests and keep getting a low score for “cache static content”. When I look at the details it shows several images as only being cached for a few days (3.1 days, 2.6 days, etc).
But those images are all cached for a long time. Checking the Response headers on the waterfall chart shows my correct setting of 30 days:
I also double checked on other tools and the caching is fine. Is there something wrong with WPT? Or is there some other reason it thinks the caching is so short?