Could Twitter not have used the Clear-Site-Data header to instruct Firefox do wipe the cache when the user logs out?<p><a href="https://w3c.github.io/webappsec-clear-site-data/#example-signout" rel="nofollow">https://w3c.github.io/webappsec-clear-site-data/#example-sig...</a>
The response from Mozilla:<p><a href="https://hacks.mozilla.org/2020/04/twitter-direct-message-caching-and-firefox/" rel="nofollow">https://hacks.mozilla.org/2020/04/twitter-direct-message-cac...</a><p><a href="https://news.ycombinator.com/item?id=22774409" rel="nofollow">https://news.ycombinator.com/item?id=22774409</a>