"Resorting to unclean kill browser." when using fig.write_image()

[ocapese]

Using:
MacOS
uv for package management
Python 3.13.1
Kaleido 1.2.0
nbformat 5.10.4
choreographer 1.2.1
plotly 6.5.2

I have recently moved to a new computer (previously I was using Windows11, Plotly 6.0.0 and Kaleido 0.2.1) and now writing images is taking forever and throwing the "Resorting to unclean kill browser." message

For instance, this simple script:

import plotly.graph_objects as go
fig = go.Figure()
fig.write_image('aaa.png')

Output: Resorting to unclean kill browser.

is taking around 9 seconds.

The images are still being produced and saved correctly but the times are too long. Is there a fix?

Thank you

[ocapese]

In another instance the following error message was displayed, the code was the same but I was not able to have it appear again:

ERROR:tornado.general:Uncaught exception in ZMQStream callback
Traceback (most recent call last):
File "~/.venv/lib/python3.13/site-packages/traitlets/traitlets.py", line 632, in get
value = obj._trait_values[self.name]
~~~~~~~~~~~~~~~~~^^^^^^^^^^^
KeyError: '_control_lock'

During handling of the above exception, another exception occurred:

File "~/.venv/lib/python3.13/site-packages/traitlets/traitlets.py", line 831, in error
raise TraitError(e)
traitlets.traitlets.TraitError: The '_control_lock' trait of an IPythonKernel instance expected a Lock, not the NoneType None.
Resorting to unclean kill browser.

[charity-g]

The exact same behavior is occurring for me:

Using:
Windows
pip for package management
Python Python 3.11.5
Kaleido 1.3.0
nbformat not installed
choreographer 1.3.0
plotly 6.6.0

even if you manually pin chrome version

import plotly.graph_objects as go
import plotly.io as pio
import os

chrome_path  = pio.get_chrome() 
print(chrome_path)

os.environ["BROWSER_PATH"] = str(chrome_path)

import plotly.graph_objects as go

fig = go.Figure(go.Scatter(x=[1, 2, 3], y=[1, 3, 2]))
fig.write_image("test.png")

[camdecoster]

Thanks for the report. We're going to try to reproduce the issue locally and follow up.