Output flickering with ipywidgets interact

[ianholst]

When using ipywidgets.interact to update a matplotlib plot (or actually any output, it seems) with a slider, the output severely flickers. This makes it difficult to see the effect of whatever parameter you are changing.

This video sort of captures it:

Screen.Recording.2025-11-11.145135.mp4

Steps to reproduce:

Run in a Jupyter notebook in VS Code:

import matplotlib.pyplot as plt
import ipywidgets
import numpy as np

def plot(a):
    plt.figure(figsize=[2,2])
    plt.ylim(0,1)
    plt.plot(np.linspace(0,1), a * np.linspace(0,1))
    plt.show()

ipywidgets.interact(plot, a=(0,1,0.1));

Environment data

• VS Code version: 1.105.1
• Jupyter Extension version: 2025.9.1
• Python Extension version: 2025.16.0
• OS: Windows
• Python and/or Anaconda version: 3.12.0
• Type of virtual environment used: none
• Jupyter server running: local