Browsertrix (and Webrecorder tools in general) also violate the standard by modifying response data. It's supposed to be the raw bytes as they are sent over the network (minus TLS).
The entire WARC ecosystem is kind of a mess.
The entire WARC ecosystem is kind of a mess.
Our tools do the best that we can with an old format that is in use by many institutions. The WARC format does not account for H2/H3 data, which is used by most sites nowadays.
The goal of our (Webreocrder) tools is to preserve interactive web content with as much fidelity as possible and make them accessible/viewable in the browser. That means stripping TLS, H2/H3, sometimes forcing a certain video resolution, etc.. while preserving the authenticity and interactivity of the site. It can be a tricky balance.
If the goal is to preserve 'raw bytes sent over the network' you can use Wireshark / packet capture, but your archive won't necessarily be useful to a human.