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
for record in records:
            values = record[self.sparse]
            record[self.name] = values.get(self.name)
        if self.relational:
            for record in records:
                record[self.name] = record[self.name].exists()
    def _inverse_sparse(self, records):
        for record in records:
            values = record[self.sparse]
            value = self.convert_to_read(record[self.name], record, use_name_get=False)
            if value:
                if values.get(self.name) != value:
                    values[self.name] = value
                    record[self.sparse] = values
            else:
                if self.name in values:
                    values.pop(self.name)
                    record[self.sparse] = values
    #
    
    #
    
    
    
    
    #
    def resolve_deps(self, model):