These quick enhancements are aimed at improving and customising your Foswiki as quickly as possible. New site administrators are encouraged to review this document for ideas before deploying their site. Small changes planned in advance can make a big differences for user satisfaction.
Preview looks like the real page, but the links lead to an oops dialog warning users of not-yet-saved topics. In addition, a background with a "PREVIEW" watermark is shown to have visual clue that you are previewing a topic. You can change the background image by specifying the name of an attached background image file in the PREVIEWBGIMAGE setting in the DefaultPreferences.
Low client and server base requirements are core features that keep Foswiki widely deployable, particularly across a range of browser platforms and versions. Many extensions exist which enhance and expand Foswiki's capabilities; they may have additional requirements.