Is it possible to make the asset cache backed by localStorage to avoid reloading assets?
The previous discussion in #332 decided to abandon this due to needing server-side support.
However, it is possible to manually set the "If-Modified-Since" header on XMLHttpRequest, avoiding a specialized server:
You will also have to store the value returned in the "Last-Modified" header when loading the asset to send this later in the "If-Modified-Since" header.
That said, this still may be functionality better left to a plugin, but I don't know how hackable the Loader is from plugins.
This is an interesting request. It's not something I will do for the 2.0 release, but I have added it to the README file under the Road Map, so it's not forgotten. Going to close this for now though.