I need to learn what?

汉典 says that 㝉 is a variant form of traditional 宁, instead of the officially simplified form. I don't know which explanation is more correct. 甯 is relatively common surname. Even it says that it was treated as a variant form and was then obsoleted during simplification, but many people still use it, especially on the Internet.

Interesting that it's listed. Taiwan MOE variant dictionary does not list 㝉:

http://dict.variants.moe.edu.tw/yitib/frb/frb00737.htm

http://dict.variants.moe.edu.tw/suoa/u040011.htm

Is there any way to enable me to view this variant? All I see is a square on screen.

To which link do you refer? I've tried to attach a screen capture of the second link. [For me, for moe.edu.tw sites, I need to explicitly change the encoding to Big5, or else everything looks bad.]

This is the only single stroke character listed under the 宀 radical, and is listed as a variant of 官.

Humm, I can't seem to figure out how to add attachments in blog comments..... I can add it to my original post.

Ah, it is unicode U+3749 -> http://www.decodeunicode.org/de/u+3749

Problem solved.