Order by foreign key is not respected when using expression as default ordering

[Mathieu Rampant]

I recently switched a bunch of

ordering = ["name"]

to

ordering = [Lower("name")]

in the Meta class of some models.

Now when I order a related Model, the result is not order as it should be.

Consider the following example:

class ItemCategory(models.Model):
    name = models.CharField(max_length=100)

    class Meta:
        ordering = [Lower("name")]

class Item(models.Model):
    name = models.CharField(max_length=100)
    category = models.ForeignKey("ItemCategory", blank=True, null=True, on_delete=models.CASCADE)

    class Meta:
        ordering = [Lower("name")]

If I do Item.objects.all().order_by("category", "name") then the results are ordered by Item name only, not ItemCategory name and Item name as it should be.

[Mariusz Felisiak]

Duplicate of #29538, fixed in Django 4.1 (see 2798c937deb6625a4e6a36e70d4d60ce5faac954).