Ok did some testing and my conclusion is that it wrorks fine now with xslt
rendering on but not with xslt rendering off.
How did I test?
I added 2 checkboxes to the cs Insert Formulator Form chkboxon and chkboxoff.
chkboxon is checked (True/1) and chkboxoff is not checked (False/0)
These are also the values I can see in Kupu.
In a ZPT i do the following tests:
<h1 style="color: grey">Checkbox on: <span tal:content="chkbox_on" /> </h1>
<h1 style="color: grey">Checkbox off: <span tal:content="chkbox_off" /> </h1>
With xslt i get the correct booleans true for the first and false for the second
With xslt I get twice false, which is not correct.