# ----------------------------------------------------------------------
# | Content transformation                                             |
# ----------------------------------------------------------------------

# Prevent intermediate caches or proxies (such as those used by mobile
# network providers) and browsers data-saving features from modifying
# the website's content using the `no-transform` directive for
# `Cache-Control` header.
#
# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control
# https://tools.ietf.org/html/rfc7234#section-5.2.2.4
#
# (!) Carefully consider the impact on your visitors before disabling
#     content transformation. These transformations are performed to
#     improve the experience for data- and cost-constrained users
#     (e.g. users on a 2G connection).
#
#     You can test the effects of content transformation applied by
#     Google's Lite Mode by visiting: https://googleweblight.com/i?u=https://www.example.com
#
#     https://support.google.com/webmasters/answer/6211428
#
# (!) If you are using `ngx_pagespeed`, note that disabling this will
#     prevent `PageSpeed` from rewriting HTML files, and, if the
#     `pagespeed DisableRewriteOnNoTransform` directive isn't set to
#     `off`, also from rewriting other resources.
#
#     https://developers.google.com/speed/pagespeed/module/configuration#notransform

add_header Cache-Control "no-transform";