## Problem When a Plotly template sets `coloraxis_autocolorscale=True`, the `color_continuous_scale` argument passed to plotly.express functions is ignored. ## Reproduction ```python import plotly.express as px import plotly.graph_objects as go df = px.data.gapminder().query("year == 2007") template = go.layout.Template(layout=go.Layout(coloraxis_autocolorscale=True)) # User specifies colorscale - THIS IS IGNORED fig = px.choropleth( df, locations="iso_alpha", color="lifeExp", color_continuous_scale=["red", "yellow", "green"], template=template, ) fig.show() # Renders with auto-detected scale, not red-yellow-green ``` ## Root cause As per the [plotly docs](https://plotly.com/python/reference/layout/coloraxis/), when `autocolorscale=True`, the colorscale is auto-detected based on the data, ignoring any explicit `colorscale` setting (this itself is quite confusing behaviour I think, but that's a separate issue - let's assume for now it should be left with that logic): > In case `colorscale` is unspecified **or** `autocolorscale` is True, the default palette will be chosen according to whether numbers in the `color` array are all positive, all negative or mixed. In the following code `autocolorscale` is not set on `coloraxis1`. This means the template's `autocolorscale=True` is inherited, causing the user's `color_continuous_scale` to be completely ignored: https://github.com/plotly/plotly.py/blob/f08397718a3b37487c5ea98e4f146ad3258c8e56/plotly/express/_core.py#L2707-L2716 ## Proposed fix When `color_continuous_scale` is explicitly provided, set `autocolorscale=False` on `coloraxis1` to ensure the user's colorscale is respected. I can raise a PR for this if you like!