(In reply to comment #1)
Can you shed a little more light on the problem espcially where to find these
Where to find them in the code or what else? Platonides already said the names of some of them, e.g. [[MediaWiki:Missing-article]].
So this task is basically about wrapping an error message into a class, similar to $outputPage->wrapWikiMsg( "<div class=\"error mw-error-cannotdelete\">\n$1\n</div>" in /includes/page/Article.php or $wgOut->wrapWikiMsg( "<div class='error' id='mw-edit-longpageerror'>\n$1\n</div>", in ./includes/EditPage.php ?
That includes: cannotdelete, cannotundelete, missing-article...
How would a potential patch contributor find the places to fix?
For example, running grep -r "cannotundelete" . I get:
./maintenance/dictionary/mediawiki.dic:cannotundelete ./includes/api/ApiUndelete.php: $this->dieUsageMsg( 'cannotundelete' ); ./includes/api/ApiBase.php: 'cannotundelete' => [ ./includes/specials/SpecialUndelete.php: 'cannotundelete', ./includes/specials/SpecialUndelete.php: 'cannotundelete'
so I guess I would have to patch includes/specials/SpecialUndelete.php in that case?
And for missing-article I cannot find anything (except for translations). Could someone clarify?
Ok, cannotdelete has already a wrapping container with a class:
As missing-article seems to isn't used in MediaWIki/core (anymore), we should first think about this message, before changing anything :P So, this task is easy and easy enough for GCI! :D