WARC is also used by the Webrecorder project. They made an app called Wabac which does entirely client-side WARC or HAR replays using service workers and it see

WARC is also used by the Webrecorder project. They made an app called Wabac which does entirely client-side WARC or HAR replays using service workers and it seems to have pretty good browser support, but I haven't really dug into the specifics. https://github.com/webrecorder/wabac.js-1.0 https://github.com/webrecorder/wabac.js-1.0