I create a new input in web.datepicker template for hijri calendar date, It appears when the record opened or created but when I try to save the record, input of hijri date disappears on form view ... any advice?

<template>     

<t t-name="web.datepicker">            

<t t-set="placeholder" t-value="widget.getParent().node and widget.getParent().node.attrs.placeholder"/>            

<t t-set="datepickerID" t-value="_.uniqueId('datepicker')"/>           

<div class="o_datepicker" aria-atomic="true" t-att-id="datepickerID" data-target-input="nearest">                 

<input type="text" class="o_datepicker_input o_input datetimepicker-input" t-att-name="widget.name" t-att-placeholder="placeholder" t-attf-data-target="##{datepickerID}" /> 

<input type="text" class="oe_hijri oe_hi_label oe_simple_date oe_datepicker_master" t-att-name="widget.name" /> 

<span class="o_datepicker_button"/> 

</div> 

</t> 

</template>

Also, when I clicked on hijri calendar, It opens both georgian and hijri calendars ... but how to open only hijri?

It works in Odoo 12 but the problem on Odoo13