Edit wiki _sidebar

Newbie question, I think:

I created a _sidebar page in my project wiki with the brilliant text “sidebar text”. It worked, and replaced the default page list.

But now I can’t figure out how to get to the page to edit it. Clearly “sidebar text” isn’t terribly useful…

Odd indeed. The only way I could find so far is to clone the wiki into a local folder. Then edit _sidebar.md and push it back.