Because Administrators still have editinterface https://zh-classical.wikipedia.org/wiki/%E7%89%B9%E6%AE%8A:%E6%AC%8A%E4%BB%BB%E4%B8%80%E8%A6%BD?uselang=en

According to the message: A new user group, interface-admin, has been created. Starting four weeks from now, only members of this group will be able edit CSS/JS pages that they do not own (that is, any page ending with .css or .js that is either in the MediaWiki: namespace or is another user's user subpage).

We don't want to create the new user group.we hope administrator can manage js/css .

The administrator continues to manage js/css without setting up an interface-admin at zh-classical Wikipedia.

@WAN233: Does that sentence describe the current situation which is a problem? Does that sentence describe a future situation which is asked for? Please follow https://mediawiki.org/wiki/How_to_report_a_bug and structure your tasks into 1) steps to reproduce, 2) actual outcome, 3) expected outcome. Thanks.

@Aklapper As a small wiki.We think this user group is a trouble.

The consensus from the community of lzh.wikipedia is to keep the ability of editing .js/.css page in either MediaWiki or user namespace for sysop, even after the transition period. It also asks for the cancellation of establishment of new user group which named as "interface administrator" for lzh.wikipedia.