@힙찔이닷컴 You should elaborate a bit more here and provide at least an error message - or better still, a detailed overview of what isn't working, or what results you got instead of what you expected.
It's impossible for us to help you without this.
This is what happened..
I don't know if it matters, but I am using the Custom Static Pages plugin. It seemed harsh to move the widgets to drafts, but was devastating to have all the widgets erased.
That might be a bug. It's definitely not static pages doing it. I don't use that plugin and it happens to me too.
This is definitely a bug. Please go ahead and submit it as an issue on Github.