For those looking for an SSG with WYSIWYG, please take a look at Publii. I have no affiliation other than being a user, but I wish more people were aware of it.

I am a fan of jekyll-admin: https://github.com/jekyll/jekyll-admin/

Its project page doesn't seem to have a screenshot of the post/page editor, but its editor is simplemde so one can just look at it directly: https://simplemde.com/