Dear all,
The Index: and Page: pages editing interfaces are currently broken if the "Two column
edit conflict" beta feature is enabled.
So, if your editing interface for these two namespaces seems broken to you, please disable
this feature (click on the "beta" link near your user name to reach the beta
feature preference panel).
This problem is tracked by
https://phabricator.wikimedia.org/T176393
Cheers,
Thomas