Duplicated boxplots

[egor-dolzhenko]

Describe the bug

The same boxplot is output 7 times. Other matplotlib plot types seem to work correctly.

Will you submit a PR?

• [ ] Yes

Environment

{
  "marimo": "0.16.5",
  "editable": false,
  "location": ".../python3.13/site-packages/marimo",
  "OS": "Darwin",
  "OS Version": "24.6.0",
  "Processor": "arm",
  "Python Version": "3.13.7",
  "Locale": "en_US",
  "Binaries": {
    "Browser": "141.0.7390.108",
    "Node": "--"
  },
  "Dependencies": {
    "click": "8.3.0",
    "docutils": "0.22.2",
    "itsdangerous": "2.2.0",
    "jedi": "0.19.2",
    "markdown": "3.9",
    "narwhals": "2.7.0",
    "packaging": "25.0",
    "psutil": "7.1.0",
    "pygments": "2.19.2",
    "pymdown-extensions": "10.16.1",
    "pyyaml": "6.0.3",
    "starlette": "0.48.0",
    "tomlkit": "0.13.3",
    "typing-extensions": "4.15.0",
    "uvicorn": "0.35.0",
    "websockets": "15.0.1"
  },
  "Optional Dependencies": {
    "loro": "1.8.1",
    "python-lsp-ruff": "2.3.0",
    "python-lsp-server": "1.13.1",
    "ruff": "0.14.0"
  },
  "Experimental Flags": {}
}

Code to reproduce

import marimo as mo
import numpy as np
import matplotlib.pyplot as plt

fig, ax = plt.subplots()
ax.boxplot([0])

[akshayka]

Thanks for filing.

For a workaround, make ax the output of the cell:

import marimo as mo
import numpy as np
import matplotlib.pyplot as plt

fig, ax = plt.subplots()
ax.boxplot([0])
ax

Additional context. Some matplotlib plot functions, like hist and boxplot, return data structures with many plot-like objects. I don't know why matplotlib is designed this way, but that's why you're seeing the repeated plots:

[egor-dolzhenko]

This sounds great -- thank you for the workaround!