# Part 1 - install/upgrade
# perform clean install (main tab)
# go to the Admin Console login screen
# confirm, that these response headers are present (using the Web Browser Developer Tools):
* `X-Content-Type-Options: nosniff`
* `X-Frame-Options: sameorigin`
# repeat previous 2 steps, but for the Front-End (separate tab)
# login to Admin Console (main tab)
# go to the {nav Configuration > Website > Advanced} section
# confirm, that `Extra HTTP Headers` system setting:
* is present
* has as multi-line value
* has `X-Content-Type-Options: nosniff` line present
* has `X-Frame-Options: sameorigin` line present
# replace contents of the `Extra HTTP Headers` system setting with `X-Redirect-By: In-Portal` and save changes
# confirm, that page response now contains `X-Redirect-By: In-Portal` header instead of the `X-Content-Type-Options: nosniff` and `X-Frame-Options: sameorigin` headers
# confirm, that for Front-End as well (separate tab)
# go to the {nav Configuration > Website > Site Domains} section
# create a site domain, that will match visited domain on the Front-End
# confirm, that a `Extra HTTP Headers` field is present and is empty
# confirm, that on Front-End (separate tab) the headers from the `Extra HTTP Headers` system setting are being sent
# change the site domain (main tab) and put `X-Redirect-By: My-Site-Domain` value into the `Extra HTTP Headers` field
# visit the Front-End (separate tab)
# confirm, that `Extra HTTP Headers` set on site domain level override ones, that are set via a system setting