One of them is the “Caching & Always Online” module.
If this is not enough, as a customer you can enable the Always Online functionality and select which pages you want to archive in the Mithril static cache. This cache will be updated only if your website is online, and all pages you selected will be served by Mithril instead of your webserver. If your web server goes down or it’s unreachable, Mithril continues to serve your website contents, keeping your website online in a static version until it is back online.
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