Hi Bruno,
In persistence-model.xml the code is making a call to the search API (look for "draft-found"), with draft=only for the specific document id being loaded. If it finds a draft for the current document id then it prompts the user, asking if she wants to open the draft rather than the saved document.
Maybe you can use something like Charles or mitmproxy to look at the request/response being made while the page is loaded. And of course, you'll let us know if Orbeon Forms is doing anything wrong there!
Alex
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