Setting headers for specific extensions seems impossible

[stp (Michael)]

The solution I used was rewrite + proxy on localhost. Might be a solution for you too:

Example for per file headers (abstract: using rewrite + proxy to get more done)

Trying around with per file headers and various other things, I finally got a solution using rewrite and proxy: localhost:1313 { # cache headers for static files rewrite { if_op or if {path} has /images/ if {path} has /css/ if {path} has /fonts/ if {path} has /icons/ to /x-cache-header/{uri} } proxy /x-cache-header/ { without /x-cache-header upstream localhost:1314 transparent header_downstream Cache-Control "max-age=172800" header_downstream …