Speed, caching and privacy

The page is one document. The stylesheet and the script are inside it, the type is already on the reader's machine and the network marks are drawn rather than loaded, so a closed page makes no request to anyone but you.

Nothing is cached: a closed page is sent with no-store headers, because the one that bites is a CDN still serving the page an hour after the mode was switched off. The real pages shown to somebody let through by a preview link, the password, their role or their IP address are marked the same way, so a page cache cannot store the unlaunched site and hand it to everyone else. So is the answer to opening a preview link, which carries its cookie.

When what visitors get changes — the mode switched on or off, a switch-on time arriving, or a change to which pages it covers — the plugin empties NimbleCache, WP Rocket, WP Super Cache, W3 Total Cache, LiteSpeed Cache, WP Fastest Cache, SiteGround Speed Optimizer, Breeze, WP-Optimize and Cloudflare (through Cloudflare's own plugin, which is what clears APO), whichever are installed. Another cache can listen for the trcs_purge_caches action. LiteSpeed Cache is asked for its pages only: its CSS and JS files, the object cache and Cloudflare stay as they are.

On the way in, the plugin does its work on template_redirect — before a byte of the theme is rendered — so the page costs less than a normal one.