How to use a role from a multi-file playbook

I have a playbook organized as follows (simplified for the sake of this question):

├── deploy.yml
├── hosts
├── requirements.yml
├── roles
│   └── web
│       ├── meta
│       │   └── main.yml
│       └── tasks
│           └── main.yml
└── site.retry

My simplified deploy.yml is:

---
- name: Everything I need
  hosts: somewhere
  roles:
    - web

And my simplified roles/web/tasks/main.yml is

---
- name: Various things that work
  become: yes
  [whatever]

- name: the thing that I have a problem with
  become: yes
  davidedelvento.nbextension: name=foo state=present

This fails with:

ERROR! no action detected in task. This often indicates a misspelled module name, or incorrect module path.

So I tried to change roles/web/tasks/main.yml to

---
- name: Various things that work
  become: yes
  [whatever]

- name: the thing that I have a problem with
  become: yes
  roles:
    - { role: davidedelvento.nbextension, name: foo, state: present}

which fails in the same way. I understand the failure (since I cannot call a role from a task, which instead I'm doing -- but the error could be clearer....)

However I am not clear how can I accomplish what I'd like, namely doing whatever nbextension is doing at that point in time. I could move that role from roles/web/tasks/main.yml to roles/web/meta/main.yml and that works, but it is executed before the Various things that work and I need it to be executed after. How to accomplish that?

Note that I wrote nbextension, however the same problem happen with similar other roles from the galaxy.

EDIT: Note also that the extension is correctly installed and can be used from a standalone, single-file playbook such as

---
- name: Example
  hosts: all
  become: yes
  roles:
    - { role: davidedelvento.nbextension, name: foo, state: present}

however I need it to "integrate" in the larger project described above for the "web" role (I have more roles that I'm not showing)

EDIT2: note that the galaxy ansible role used for this question has been renamed to jupyterextension but as I said the issue (and solution) is the same for any role

Ok, so I've found two ways to deal with this issue.

split the role in two (or more) parts and use the galaxy's role as a dependency to the things that it needs to prepend. In general, I like this idea, but in my particular use case I don't, since I would need create 3 roles for something that is really one.
Use include_role module, with the caveat that at the moment it is "flagged as preview", namely it is not guaranteed to have a backwards compatible interface. However it works quite well for my current setup:

- name: the thing that I have not a problem with anymore become: yes include_role: name: davidedelvento.nbextension with_items: - foo - bar loop_control: loop_var: name