For some reason, the insert hyperlink button is often greyed out when editing a workflow, even when editing a Text or Expandable Text field. The shortcut key doesn't work either.
I can workaround it by pasting in the hyperlink directly into the body of the field, then editing the resultant http… text into what I want.
As a separate issue, hyperlinks can't be added to at all to Question/Answer fields. This is a shame. I'd like to add hyperlinks to questions so if I forget exactly what I meant by the question I can look it up.
