It&#x27;s notable that appcache is now deprecated [0]<p>It&#x27;s been replaced by Service Workers, but those can get reallly hard to deal with if they start caching themselves (!)<p>Chrome&#x27;s devtools has ways to delete old service workers and such, but I&#x27;ve found that on Firefox it&#x27;s next to impossible to debug.<p>[0] <a href="https:&#x2F;&#x2F;developer.mozilla.org&#x2F;en-US&#x2F;docs&#x2F;Web&#x2F;HTML&#x2F;Using_the_application_cache" rel="nofollow">https:&#x2F;&#x2F;developer.mozilla.org&#x2F;en-US&#x2F;docs&#x2F;Web&#x2F;HTML&#x2F;Using_the_...</a>