Deposits functionality differs in Role tailored vs Classic

davmac1

In the role tailored version (page), if you enter a deposit line, and then apply entries, you can edit the amount to apply. In the classic client (form), the field is uneditable - which I believe is caused by the codeunit calling it with Lookupmode = true.
The code behind the form is the same as the page, so it looks like the intention has always been to allow this field to be edited.
It looks like role tailored inadvertently fixed a long time bug.
Is there a way of duplicating the role tailored functionality in the classic client? Turning off lookupmode does not fix the problem (though it does produce different, but not good results).