Cosmetic changes should only be applied when there is a substantial change to make at the same time. Scripts that apply cosmetic changes, such as [https://fisheye.toolserver.org/browse/pywikipedia/trunk/pywikipedia/cosmetic_changes.py?r=6769 cosmetic_changes.py], should be used with caution. The pywiki functions <tt>standardizeCategories</tt>, <tt>validXhtml</tt>, <tt>translateAndCapitalizeNamespaces</tt>, <tt>removeNonBreakingSpaceBeforePercent</tt>, or equivalent functionality, should not be used (as of May 2009), as they do not function correctly or there is no consensus for such changes. The functions <tt>removeUselessSpaces</tt> and <tt>cleanUpSectionHeaders</tt> are also not recommended, as they mainly move around whitespace. Cosmetic changes should only be applied when there is a substantial change to make at the same time.