cubicweb-preview #3216745 Improve form preview button for non entity forms [resolved]

Current js preview button code only works for entity forms, although it could be used in other contexts, such as a FieldsForm.

prioritynormal
typeenhancement
done in1.1.0
load0.100
load left0.000
closed by#22adf9f7d1f2 Improve form preview button so that it still works for all form types.
patchImprove form preview button so that it still works for all form types. [applied]