There is another similar question on the forum, but it's not getting any answers so I thought I'd try again.
I have created a collection for a blog and used a template to create it. It shows all the fields in the drop down when selecting except a rich text field called Post Body. I created a new rich text field as a test and that didn't show either, so I tried a Plain Text field and that did.
I'm not doing anything clever here, does anyone (Webflow??) know what the problem is?