1. `copy_cache` in `models.py` recursively copies the caches to environment, 
2. which in
```python
def _compute_related(self, records):
        """ Compute the related field ``self`` on ``records``. """
        others = records.sudo() if self.related_sudo else records
        if records.env != others.env:
            copy_cache(records - records.filtered('id'), others.env)
        values = list(others)
        for name in self.related[:-1]:
            values = [first(value[name]) for value in values]
        for record, value in zip(records, values):
            record[self.name] = value[self.related_field.name]
```
3. copies failing cache values that have been produce previously by this line:

`models.py : def _prefetch_field()`
```python

        try:
            # THIS ONE
            result = records.read([f.name for f in fs], load='_classic_write')
        except AccessError:
            # not all records may be accessible, try with only current record
            result = self.read([f.name for f in fs], load='_classic_write')
```
I checked it's exactly the same `FailedValue` object, which is later accessed without intent (not refreshed) by the fact that the buggy environment is copied to sudo (and not refreshed).


odoo/fields.py
def process(ids):
            return record._prefetch[self.comodel_name].update(ids) or ids
        if isinstance(value, BaseModel):
            if not validate or (value._name == self.comodel_name):
                return process(value._ids)
        elif isinstance(value, (list, tuple)):
            
            comodel = record.env[self.comodel_name]
            
            ids = OrderedSet(record[self.name].ids if record.id else ())
            
            for command in value:
                if isinstance(command, (tuple, list)):
                    if command[0] == 0:
                        ids.add(comodel.new(command[2]).id)
                    elif command[0] == 1:
                        comodel.browse(command[1]).update(command[2])
                        ids.add(command[1])
                    elif command[0] == 2:
                        
                        ids.discard(command[1])
                    elif command[0] == 3:
                        ids.discard(command[1])
                    elif command[0] == 4:
                        ids.add(command[1])
                    elif command[0] == 5:
                        ids.clear()
                    elif command[0] == 6: