Error with Web PDF and option --WebPDFExporter.paginate=False

[lsignac]

converting to pdf (Webpdf) and pagination works well :

> jupyter nbconvert --to WebPDF  --theme light --execute --allow-errors TP.ipynb

[NbConvertApp] Converting notebook TP.ipynb to WebPDF
[NbConvertApp] Building PDF
[NbConvertApp] PDF successfully created
[NbConvertApp] Writing 124332 bytes to TP.pdf

but it fails without pagination :

> jupyter nbconvert --to WebPDF  --WebPDFExporter.paginate=False --theme light --execute --allow-errors TP.ipynb 

[NbConvertApp] Converting notebook TP.ipynb to WebPDF
[NbConvertApp] Building PDF
Traceback (most recent call last):
  File "/usr/bin/jupyter-nbconvert", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/usr/lib/python3.12/site-packages/jupyter_core/application.py", line 283, in launch_instance
    super().launch_instance(argv=argv, **kwargs)
  File "/usr/lib/python3.12/site-packages/traitlets/config/application.py", line 1075, in launch_instance
    app.start()
  File "/usr/lib/python3.12/site-packages/nbconvert/nbconvertapp.py", line 420, in start
    self.convert_notebooks()
  File "/usr/lib/python3.12/site-packages/nbconvert/nbconvertapp.py", line 597, in convert_notebooks
    self.convert_single_notebook(notebook_filename)
  File "/usr/lib/python3.12/site-packages/nbconvert/nbconvertapp.py", line 563, in convert_single_notebook
    output, resources = self.export_single_notebook(
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/nbconvert/nbconvertapp.py", line 487, in export_single_notebook
    output, resources = self.exporter.from_filename(
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/nbconvert/exporters/templateexporter.py", line 386, in from_filename
    return super().from_filename(filename, resources, **kw)  # type:ignore[return-value]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/nbconvert/exporters/exporter.py", line 201, in from_filename
    return self.from_file(f, resources=resources, **kw)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/nbconvert/exporters/templateexporter.py", line 392, in from_file
    return super().from_file(file_stream, resources, **kw)  # type:ignore[return-value]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/nbconvert/exporters/exporter.py", line 220, in from_file
    return self.from_notebook_node(
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/nbconvert/exporters/webpdf.py", line 174, in from_notebook_node
    pdf_data = self.run_playwright(html)
               ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/nbconvert/exporters/webpdf.py", line 163, in run_playwright
    pdf_data = pool.submit(run_coroutine, main(temp_file)).result()
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/concurrent/futures/_base.py", line 456, in result
    return self.__get_result()
           ^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/concurrent/futures/_base.py", line 401, in __get_result
    raise self._exception
  File "/usr/lib/python3.12/concurrent/futures/thread.py", line 58, in run
    result = self.fn(*self.args, **self.kwargs)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/nbconvert/exporters/webpdf.py", line 161, in run_coroutine
    return loop.run_until_complete(coro)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/asyncio/base_events.py", line 687, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/nbconvert/exporters/webpdf.py", line 134, in main
    pdf_data = await page.pdf(**pdf_params)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/playwright/async_api/_generated.py", line 11359, in pdf
    await self._impl_obj.pdf(
  File "/usr/lib/python3.12/site-packages/playwright/_impl/_page.py", line 1084, in pdf
    encoded_binary = await self._channel.send("pdf", params)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/playwright/_impl/_connection.py", line 59, in send
    return await self._connection.wrap_api_call(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/site-packages/playwright/_impl/_connection.py", line 514, in wrap_api_call
    raise rewrite_error(error, f"{parsed_st['apiName']}: {error}") from None
playwright._impl._errors.Error: Page.pdf: width: expected string, got number
Exception ignored in: <function BaseSubprocessTransport.__del__ at 0x75c3b5eb4ea0>
Traceback (most recent call last):
  File "/usr/lib/python3.12/asyncio/base_subprocess.py", line 126, in __del__
  File "/usr/lib/python3.12/asyncio/base_subprocess.py", line 104, in close
  File "/usr/lib/python3.12/asyncio/unix_events.py", line 767, in close
  File "/usr/lib/python3.12/asyncio/unix_events.py", line 753, in write_eof
  File "/usr/lib/python3.12/asyncio/base_events.py", line 795, in call_soon
  File "/usr/lib/python3.12/asyncio/base_events.py", line 541, in _check_closed
RuntimeError: Event loop is closed
Task was destroyed but it is pending!
task: <Task pending name='Task-121' coro=<Connection.run() running at /usr/lib/python3.12/site-packages/playwright/_impl/_connection.py:274> wait_for=<Future pending cb=[Task.task_wakeup()]>>

I had to modify /exporters/webpdf.py :

pdf_params.update(
                    {
                        "width": min(width, 200 * 72),
                        "height": min(height, 200 * 72),
                    }
                )

is modified to :

pdf_params.update(
                    {
                        "width":  str(min(width, 200 * 72)),
                        "height": str(min(height, 200 * 72)),
                    }
                )

Then, it works, without pagination.
(More precisely, there is no error, I get the PDF, with one long page... and a few lines on a second page. Whatever the size of the initial notebook, the result is always one long page plus a few lines. I can get a single page with "height": str(min(height + 2 * 72, 200 * 72)),.

I don't know if this error is from my particular installation (Arch, I installed nbconvert with the distro packet manager, not from github), so I did not submit a pull request. Let me know if its helps