Require acceptance field in hidden group blocks submit

I need to show an acceptance field if a condition is met, when that acceptance is shown it should be required. When it is hidden it should not be required.
Now when it is hidden it just block the sent button.
You can reproduce this with this setup:

[acceptance acceptance-840]Accept1 [/acceptance]
[checkbox* checkbox-793 use_label_element “yes” “no”][group group-987]
[acceptance acceptance-840]Accept2 [/acceptance]
[/group]

[submit “Submit”]

show [group-987] if [checkbox-793] equals “yes”

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