Need to create and update figures in seperate cells?

Something I've seen in previous versions as well as the current version: In order to have a figure that dynamically updates while some code is executing (e.g. tracking the loss function of an optimization), I have to create the figure in a separate jupyter notebook cell and run it before a I run the code that updates. If I don't do this, then a blank figure shows and never updates. I'm using Jupyter lab. Wondering if I'm doing something wrong here? It would make the code cleaner and easier to run if it could all be put in a single cell.

Example:

Using the following function:

def update_function(fig, ax):
   while True:
       # Do some computation
       ax.clear() #clear previously drawn
       ax.plot(some_data)
       fig.canvas.draw() #force it to update

This works:

# cell 1
fig, ax = plt.subplots()

# cell 2
update_function(fig, ax)

But this does not:

# one combined cell
fig, ax = plt.subplots()
update_function(fig, ax)

El issue no menciona archivos ni pruebas del repositorio. Empieza reproduciendo en JupyterLab los ejemplos con celdas separadas y celdas combinadas; después, compara cómo afecta update_function, de larga duración, al renderizado. Se considera terminado cuando la celda combinada actualiza la figura según lo solicitado, o cuando el issue documenta una limitación confirmada y su workaround correcto.