To add pagination to the list view of the ideas, follow these steps:

1. Import the necessary pagination classes from Django into the views.py file. We will add pagination management to the idea_list view just after filtering. Also, we will slightly modify the context dictionary by assigning page to the object_list key:

# myproject/apps/ideas/views.py
from django.shortcuts import render, redirect, get_object_or_404
from django.conf import settings
from django.core.paginator import (EmptyPage, PageNotAnInteger, Paginator)

from .forms import IdeaFilterForm
from .models import Idea, RATING_CHOICES


PAGE_SIZE = getattr(settings, "PAGE_SIZE", 24)


def idea_list(request):
    qs = Idea.objects.order_by("title")
    form = IdeaFilterForm(data=request.GET)

    facets = {
        "selected": {},
        "categories": {
            "authors": form.fields["author"].queryset,
            "categories": form.fields["category"].queryset,
            "ratings": RATING_CHOICES,
        },
    }

    if form.is_valid():
        filters = (
            # query parameter, filter parameter
            ("author", "author"),
            ("category", "categories"),
            ("rating", "rating"),
        )
        qs = filter_facets(facets, qs, form, filters)

    paginator = Paginator(qs, PAGE_SIZE)
    page_number = request.GET.get("page")
    try:
        page = paginator.page(page_number)
    except PageNotAnInteger:
        # If page is not an integer, show first page.
        page = paginator.page(1)
    except EmptyPage:
        # If page is out of range, show last existing page.
        page = paginator.page(paginator.num_pages)

    context = {
        "form": form,
        "facets": facets, 
        "object_list": page,
    }
    return render(request, "ideas/idea_list.html", context)

2. Modify the idea_list.html template as follows:

{# ideas/idea_list.html #}
{% extends "base.html" %}
{% load i18n utility_tags %}

{% block sidebar %}
    {% include "ideas/includes/filters.html" %}
{% endblock %}

{% block main %}
    <h1>{% trans "Ideas" %}</h1>
    {% if object_list %}
        {% for idea in object_list %}
            <a href="{{ idea.get_url_path }}" class="d-block my-3">
                <div class="card">
                  <img src="{{ idea.picture_thumbnail.url }}" 
                   alt="" />
                  <div class="card-body">
                    <p class="card-text">{{ idea.translated_title 
                     }}</p>
                  </div>
                </div>
            </a>
        {% endfor %}
        {% include "misc/includes/pagination.html" %}
    {% else %}
        <p>{% trans "There are no ideas yet." %}</p>
    {% endif %}
    <a href="{% url 'ideas:add_idea' %}" class="btn btn-primary">
     {% trans "Add idea" %}</a>
{% endblock %}

3. Create the pagination widget template:

{# misc/includes/pagination.html #}
{% load i18n utility_tags %}
{% if object_list.has_other_pages %}
    <nav aria-label="{% trans 'Page navigation' %}">

        <ul class="pagination">
            {% if object_list.has_previous %}
                <li class="page-item"><a class="page-link" href="{% 
          modify_query page=object_list.previous_page_number %}">
                    {% trans "Previous" %}</a></li>
            {% else %}
                <li class="page-item disabled"><span class="page-
                 link">{% trans "Previous" %}</span></li>
            {% endif %}

            {% for page_number in object_list.paginator
             .page_range %}
                {% if page_number == object_list.number %}
                    <li class="page-item active">
                        <span class="page-link">{{ page_number }}
                            <span class="sr-only">{% trans 
                             "(current)" %}</span>
                        </span>
                    </li>
                {% else %}
                    <li class="page-item">
                        <a class="page-link" href="{% modify_query 
                         page=page_number %}">
                            {{ page_number }}</a>
                    </li>
                {% endif %}
            {% endfor %}

            {% if object_list.has_next %}
                <li class="page-item"><a class="page-link" href="{% 
             modify_query page=object_list.next_page_number %}">
                    {% trans "Next" %}</a></li>
            {% else %}
                <li class="page-item disabled"><span class="page-
                 link">{% trans "Next" %}</span></li>
            {% endif %}
        </ul>
    </nav>
{% endif %}