I have a string field that I added HTML code to so it displays a button with an link.

I've somehow can only see the button and can't edit the field any more.

I've tried the attached settings on the field, but it still only shows the rendered code, not the html

Any suggestion on how I can edit this??

Thanks for the response.  I can confirm that my user is a Super Admin.

have you had chance to look at yet for Master Details Tables?