Impacted versions:
At least version 10, version 11(Can only re-produce the problem sometimes)

Steps to reproduce:
Please see this screencast recorded on odoo runbot.
https://youtu.be/cSPQvp9jQJc

Current behavior:
When users search by account in Journal Entries List View. A special value "dummy_account_id" is set in context, in order to facilitate search by account on account.move level.
With this context value , when users create a journal entries, the system will add default value before the creation.

https://github.com/odoo/odoo/blob/fc69b37cf710623ea215cd085e998679d8c50985/odoo/models.py#L3802

This method will set "dummy_account_id" to the previously searched account in vals.

Then the system continue creating account.move and related account.move.line records.
It is fine until the system run this:
https://github.com/odoo/odoo/blob/fc69b37cf710623ea215cd085e998679d8c50985/odoo/models.py#L3830

Since "dummy_account_id" is related field, and it now has value. The system will change the first related  account.move.line record to dummy_account_id.

Eventualy, the account is wrongly set to "dummy_account_id".

Expected behavior:
This is a feature which will fill the form field value with searched value for users. But the journal entry creation should not be affected by dummy_account_id, since it is only for searching purpose.

@Yenthe666 Would you please review this issue and help to bring related odoo staff to this issue?
addons/account/models/account_move.py
for move_line in self:
            if move_line.journal_id.type in ('sale', 'purchase'):
                move_line.debit_cash_basis = move_line.debit * move_line.move_id.matched_percentage
                move_line.credit_cash_basis = move_line.credit * move_line.move_id.matched_percentage
            else:
                move_line.debit_cash_basis = move_line.debit
                move_line.credit_cash_basis = move_line.credit
            move_line.balance_cash_basis = move_line.debit_cash_basis - move_line.credit_cash_basis
    @api.one
    @api.depends('move_id.line_ids')
    def _get_counterpart(self):
        counterpart = set()
        for line in self.move_id.line_ids:
            if (line.account_id.code != self.account_id.code):
                counterpart.add(line.account_id.code)
        if len(counterpart) > 2:
            counterpart = list(counterpart)[0:2] + ["..."]
        self.counterpart = ",".join(counterpart)
    name = fields.Char(required=True, string="Label")
    quantity = fields.Float(digits=dp.get_precision('Product Unit of Measure'),
        help="The optional quantity expressed by this line, eg: number of product sold. The quantity is not a legal requirement but is very useful for some reports.")
    product_uom_id = fields.Many2one('product.uom', string='Unit of Measure')
    product_id = fields.Many2one('product.product', string='Product')
    debit = fields.Monetary(default=0.0, currency_field='company_currency_id')
    credit = fields.Monetary(default=0.0, currency_field='company_currency_id')
    balance = fields.Monetary(compute='_store_balance', store=True, currency_field='company_currency_id',
        help="Technical field holding the debit - credit in order to open meaningful graph views from reports")
    debit_cash_basis = fields.Monetary(currency_field='company_currency_id', compute='_compute_cash_basis', store=True)
    credit_cash_basis = fields.Monetary(currency_field='company_currency_id', compute='_compute_cash_basis', store=True)