Removing a widget using remove() generates "Task exception was never retrieved" (app works fine)

[learnbyexample]

Here's a minimal test app:

from textual.app import App
from textual.widgets import Label, Button

class TestApp(App):

    def compose(self):
        yield Button('Click me')

    def on_mount(self):
        self.dark = False

    def on_button_pressed(self, event):
        w = Label()
        w.remove()

if __name__ == "__main__":
    app = TestApp()
    app.run()

For Textual 0.15.0 version, I'm getting the following report on the terminal (after closing the app). This seems to happen only when remove() is encountered. So, if you run the above app without clicking the button, the error message doesn't appear.

(virt_env) $ python test_app.py
Task exception was never retrieved
future: <Task finished name='prune nodes' coro=<App._remove_nodes.<locals>.prune_widgets_task() done, defined at /home/learnbyexample/virt_env/lib/python3.8/site-packages/textual/app.py:2187> exception=AttributeError("'NoneType' object has no attribute 'styles'")>
Traceback (most recent call last):
  File "/home/learnbyexample/virt_env/lib/python3.8/site-packages/textual/app.py", line 2200, in prune_widgets_task
    if parent.styles.auto_dimensions:
AttributeError: 'NoneType' object has no attribute 'styles'

For the actual app I'm working on, I haven't observed any issue due to this error.

[github-actions]

We found the following entries in the FAQ which you may find helpful:

• How do I center a widget in a screen?
• Does Textual support images?

Feel free to close this issue if you found an answer in the FAQ. Otherwise, please give us a little time to review.

This is an automated reply, generated by FAQtory

[github-actions]

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