Paginator for raw_id_fields popup returns 404

[stefanofusai]

Python version
3.13

Django version
5.1.4

Package version
0.29.3

Current behavior (bug description)

When opening the popup for a related model (defined in the admin class via the raw_id_fields var) and trying to navigate through the pages of the related model, clicking on any page returns 404

The html for the paginator is as follows:

<p class="paginator">

    <span class="this-page">1</span> 

    <a href="?_popup=1&amp;_to_field=id&amp;p=2">2</a> 

    <a href="?_popup=1&amp;_to_field=id&amp;p=3">3</a> 

    <a href="?_popup=1&amp;_to_field=id&amp;p=4">4</a> 

    <a href="?_popup=1&amp;_to_field=id&amp;p=5" class="end">5</a> 

</p>

But upon clicking any of these links, the following error appears:

From my understanding the href isn't being concatenated to the popup URL, but I'm unsure what the cause is

Expected behavior
Pagination for popups of related models works fine

[fabiocaccamo]

@stefanofusai could you share your project (remove all the unnecessary parts) so I can debug the problem quickly?

[stefanofusai]

@fabiocaccamo the project is quite big (and private) so it's pretty hard to share it. Maybe we could schedule a call and I could show it to you?

Anyhow here's a minimal repro of a model breaking:

@admin.register(User)
class UserAdmin(BaseUserAdmin):
    pass

@admin.register(UserProfile)
class UserProfileAdmin(admin.ModelAdmin):
    raw_id_fields = ("user",)

[fabiocaccamo]

@stefanofusai ok don't worry, I'll replicate the problem myself as soon as I have time.

[fabiocaccamo]

@stefanofusai I think this issue might be caused by the {% querystring %} template tag introduced in Django 4.0.

Could you please check if the problem still occurs when this library is not used?

[stefanofusai]

@fabiocaccamo I can confirm that not using this library (and therefore using the standard Django admin) works fine; the popup redirects first to http://localhost:8000/admin/myapp/mymodel/?_to_field=id&_popup=1 and the second page to http://localhost:8000/admin/myapp/mymodel/?_popup=1&_to_field=id&p=2