After starting Publii, I select Posts at the top of the left hand vertical margin menu (with blue background.) Then I select the Post title. This brings up the post with a minimalist interface. I’m not sure of the name of this post editor.
I think you are talking about the WYSIWYG editor – this one works in the same way as in the Publii 0.35. There are a few small UI differences like now you can enable/disable sidebar or stats panel, also the TityMce editor was updated to the newest version.
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