Announcement Bar for WooCommerce – Gatemi

A line across the top of the shop: a sale, a shipping deadline, a delivery
promise. Shown between the dates you choose, and gone when they pass.

A dismissed bar never paints. The bar is server-rendered, so it works
before any script has run and a page cache can serve it. A dismissal is a fact
about one visitor, which a cache cannot know, so one tiny snippet in the head
reads the dismissal cookie and hides the bar before anything paints. A shopper
who closed it does not see it flash back on the next page.

A bar is text somebody typed, and it is treated that way. The message
passes wp_kses_post() at save and at render, because an import bypasses
the editor; a javascript: destination never becomes a link; and a colour is
validated as a colour rather than pasted into a style attribute.

The full edition

Gatemi Announcement Bar for WooCommerce
is a separate plugin, sold on gatemi.com, that adds as many bars as you like
and shows each one only where it belongs: on chosen pages or everywhere
except the checkout, by what is in the cart (its value, its categories, or
nothing at all), by the visitor’s role, or before a cutoff time for shipping
deadlines. It also adds a bar at the foot of the page and one that stays put
as they scroll.

Both editions store their bars the same way, so upgrading keeps everything —
and anything the full edition wrote is kept here untouched, ready to be
picked straight back up. This edition edits the first bar and shows one: the
first that is switched on, inside its dates and carries none of the full
edition’s targeting. A bar that carries targeting is not shown here at all,
because this edition cannot judge it and guessing could show it to somebody
the merchant excluded.