This mode is called by l10n.gettext when its format parameter is set to true. It is applied to the elements and text children of the translated message that l10n.gettext finds. This allows you to insert content in format strings, rather than concatenating multiple translations to create a translated message.

By default, this stylesheet provides matching templates in this mode for the elements node and string. The template for node applies templates with no mode to the $node parameter passed to l10n.gettext. The template for string copies the text in the $string parameter passed to l10n.gettext. Both parameters are passed to templates in this mode. Templates matching this mode should pass those parameters to child content if they process child content in l10n.format.mode.

To use format strings in your own translations, use elements with names of your choosing in your message. You can use the node and string elements without further implementation, if they fit your needs. Otherwise, take care to use element names that are unlikely to conflict with other templates using this mode.