Web: subforms and refresh fields on keyword change

We have this escenario:

a web form with, in order:

  • subform A

  • field F (dialog list)

  • subform B

when the field F has got the property of “refresh fields on keyword change” and from the browser we change the value the recalculated form on web looks like:

  • subform B

  • subform A

  • field F

subforms are not calculated.

does someone know why this appens?

if we copy-paste the code un the form this not happen. Is this the only solution?

thank you in advance