"If I enter text into the summary field and then hit "show preview" the summary text vanishes."
This only applies when JS is turned off. (Else the preview is loaded using Ajax and the original form is never replaced in the browser.)
How to reproduce:
- 'Edit with form' some page containing a summary input.
- Insert text into the summary line.
- Hit 'Preview'.
Result: No text in the summary line of the form.
Expected: Text as inserted in step 3.
The problem is that, although values for standard inputs are sent in the preview request, they are not included in the form html.
SFFormUtils::summaryInputHTML and the other ...InputHTML methods need to be fixed.