Disable caching
Apacheconf
RewriteEngine On
<FilesMatch "\.(html|htm|js|css)$">
  FileETag None
  <IfModule mod_headers.c>
    Header unset ETag
    Header set Cache-Control "max-age=0, no-cache, no-store, must-revalidate"
    Header set Pragma "no-cache"
    Header set Expires "Wed, 12 Jan 1980 05:00:00 GMT"
  </IfModule>
</FilesMatch>