Broken autocomplete inside Inline after clicking "Add another ..."

[Michał Pokusa]

This error occurs on versions from 3.2 (or even before, untested) up to latest (5.2 at this time). It seems like it is only JS/CSS related.
Happens with both TabularInline and StackedInline.

Possibly related to #36336.

Tested on Google Chrome, Firefox, Edge and on mobile device.

Steps to reproduce (code below):

1. Go to change form view (editing existing object, adding new one, doesn't matter)
2. Click "X" on any inline except last one
3. Click "Add another ..." once again

Code:

models.py

from django.db import models


class Restaurant(models.Model):
    name = models.CharField(max_length=100)
    address = models.CharField(max_length=255)

    def __str__(self):
        return self.name


class Order(models.Model):
    restaurant = models.ForeignKey(Restaurant, on_delete=models.CASCADE)
    order_number = models.CharField(max_length=20)
    products = models.ManyToManyField("Product", related_name="orders")

    def __str__(self):
        return f"Order {self.pk} from {self.restaurant.name}"


class Product(models.Model):
    name = models.CharField(max_length=100)
    price = models.DecimalField(max_digits=10, decimal_places=2)

    def __str__(self):
        return f"{self.name} - ${self.price}"

admin.py

from django.contrib import admin

from .models import Restaurant, Order, Product


class OrderInline(admin.StackedInline):
    model = Order
    extra = 3

    fields = ["order_number", "products"]
    autocomplete_fields = ["products"]


@admin.register(Restaurant)
class RestaurantAdmin(admin.ModelAdmin):
    list_display = ("name", "address")
    search_fields = ("name", "address")

    inlines = [OrderInline]


@admin.register(Order)
class OrderAdmin(admin.ModelAdmin):
    list_display = ("restaurant", "order_number")


@admin.register(Product)
class ProductAdmin(admin.ModelAdmin):
    list_display = ("name", "price")

    search_fields = ("name",)

[Natalia Bidart]

Thank you Michał Pokusa, I was able to reproduce this issue with the provided steps.

[Joe Babbitt]

Hi there Ahmed,
I noticed that this ticket has been owned but inactive for a little over a year. I'm currently working at the PyCon 2026 Django sprint and am going to take a stab at this bug. Hope that's alright!

(Commenting for other sprinters)

[blighj]

Hi Michael,
Joe waited 3 months for a review, and I only just got round to providing one. It's way too soon to take over the ticket.
Appreciate your willingness to contribute, but I'm afraid this is not the correct ticket to start on, sorry for the wasted effort.