User:Gundam785/Bugs to watch out for

MediaWiki is not perfect. There are bugs, some minor, some more annoying.

Of all these bugs, there are some all editors should watch out for; they can cause confusing effects without aparent cause. This page is an attempt to catalog them.

Feel free to edit this page as if it were in the Wikipedia: namespace.

Bugs

 * Edit conflicts causing text duplication
 * Sometimes, an edit conflict can cause part of the page to be duplicated. The exact circumstances in which this happens aren't clear. If you can reproduce this in a repeatable way, the developers would probably like to hear about it.
 * Workaround: When encountering an edit conflict, go back and start your edit again (easy if adding a comment to a talk page, not feasible for complex time-consuming edits). If you go on, check the history immediately after saving and revert or fix if part of the page was duplicated.
 * Note: it has been said that sometimes the software will not show the edit conflict, but instead duplicate the sections automatically. See this post at the Administrator's noticeboard.


 * Subst of  on templates fails
 * If you try to subst: a template which has a  markup, it breaks the template
 * Workaround: Use HTML entities instead of  when creating a template that might be used with subst:.


 * Square brackets lossage
 * Sometimes, when using square brackets within a internal link, all the text before the next internal link is eaten.
 * Workaround: Use HTML entities instead of the square brackets.


 * Redlinked categories
 * If you add a category to an article before creating the category page, the category stays a red link.
 * Workaround: do a null edit to the page after creating the category page, or do a purge of the page.