In the past, MediaWiki recognizes [[Ɑ]] and [[ɑ]] two different titles, but now, [[Ɑ]] is recognized as the uppercase form of [[ɑ]], creating troubles below. This may also happen to wikis flipping $wgCapitalLinks after they've been used for a while.

Original status:

[[Ɑ]] is a redirect to [[ɑ]]; [[ɑ]] has contents.

When [[Ɑ]] becomes the uppercase form:

[[ɑ]] is never accessible directly, but accessible as a redirect target of [[Ɑ]].

After I edit [[Ɑ]]:

[[ɑ]] becomes inaccessible, even if I change [[Ɑ]] back to the string "#REDIRECT [[ɑ]]" (in this case [[Ɑ]] becomes a self-redirect).

To finally resolve the issue:

Use api.php?action=move to move [[ɑ]] (identified by its page id) to some "ucfirst"ed title.

Version: 1.22.0
Severity: normal