Currently vite dev server is communicating via TLS + HTTP1.1 because we opted it out unintentionally by using api proxy as stated here in the Vite docs .
This seems to be rather slow because of the way the development server works (does not create a bundle, uses native import instead which loads all the sources by HTTP1.1 basically during each page reload). It also seems to cause frequent ERR_NETWORK_CHANGED failures at least on my machine (maybe Windows running out of usable TCP sockets?), which is quite painful to do any meaningful work.