Impacted versions:

At least 8.0

Steps to reproduce:

See https://youtu.be/kmXVzf3ApaM

Current behavior:

Currently if you validate an invoice (even with an invoice date) after the initial conversion rate has changed
(if the rate is changed between creation and validation). The tax amount and the credit/debit amount is not computed from the same rate.

This one is responsible for several production issues for tax reporting for the fiscal administration.

Expected behavior:

The tax amount and the credit/debit amount must be computed from the same rate.

Video/Screenshot link (optional):

https://youtu.be/kmXVzf3ApaM

Related issue : https://github.com/odoo/odoo/issues/13473

My proposal to fix this one : https://github.com/odoo/odoo/pull/13621

addons/account/account_invoice.py
if context.get('type'):
            for node in doc.xpath("//field[@name='partner_bank_id']"):
                if context['type'] == 'in_refund':
                    node.set('domain', "[('partner_id.ref_companies', 'in', [company_id])]")
                elif context['type'] == 'out_refund':
                    node.set('domain', "[('partner_id', '=', partner_id)]")
        if view_type == 'search':
            if context.get('type') in ('out_invoice', 'out_refund'):
                for node in doc.xpath("//group[@name='extended filter']"):
                    doc.remove(node)
        if view_type == 'tree':
            partner_string = _('Customer')
            if context.get('type') in ('in_invoice', 'in_refund'):
                partner_string = _('Supplier')
                for node in doc.xpath("//field[@name='reference']"):
                    node.set('invisible', '0')
            for node in doc.xpath("//field[@name='partner_id']"):
                node.set('string', partner_string)
        res['arch'] = etree.tostring(doc)
        return res
    @api.multi
    def invoice_print(self):
        """ Print the invoice and mark it as sent, so that we can see more
            easily the next step of the workflow
        """
        assert len(self) == 1, 'This option should only be used for a single id at a time.'
        self.sent = True
        return self.env['report'].get_action(self, 'account.report_invoice')
    @api.multi
    def action_invoice_sent(self):