Reference material is written in a terse, formal style that avoids referring to the reader, and instead focuses on how ~TiddlyWiki itself behaves. The passive voice is often suitable:
Most contracted verb forms are avoided in reference tiddlers. But those ending in <<doc-w "n't">> (<<doc-w "aren't">>, <<doc-w "doesn't">>, <<doc-w "hasn't">>, <<doc-w "isn't">>, etc) are acceptable, as they make it less easy to accidentally overlook the word <<doc-w not>>.