In-Place Resource Optimization
PageSpeed Optimization Filters
In-Place Resource Optimization (IPRO) works by serving optimized resources from the original URL, as opposed to the normal mode of operation, where resources are served from rewritten and optimized PageSpeed URL. This URL rewriting does generate a lot more optimization opportunities as it places the asset in context of the user-agent and surrounding page, but comes with a cost of a slight chance of breaking scripts on a small set of websites, and is only possible after inspecting how they are references via the HTML. IPRO is still able to do some per-user-agent optimizations, by indicating variability of resources at the HTTP level. So, for example, it is still possible to convert from gif, jpeg or png to WebP format for images. Or serve lower-res images to mobile user agents.
pagespeed InPlaceResourceOptimization on