When visit a page, and its discussion page is a redirect, the tab (monobook) ca-talk has no class=mw-redirect, like internal links on a page. Please add the class, so it is possible to see, if the discussion page is a redirect or holds content (after add user.css). Thanks.
Related Gerrit Patches:
|mediawiki/core : master||SkinTemplate: Set link classes on content_navigation tabs|
These tabs (content_actions) bypass LinkRenderer, and having them use it looks kind of non-trivial...probably best to just manually call Linker::getLinkColour() for now to get the extra classes.