importing hvplot.pandas and hvplot.xarray changes extension to bokeh

[Sevans711]

ALL software version info

Software Version Info

Python 3.14.6
hvplot 0.12.2

Description of expected behavior and the observed behavior

Expected: importing hvplot.pandas and hvplot.xarray should not call hvplot.extension nor adjust hvplot.Store.current_backend.

Observed: importing either of these seems to always swap the backend to bokeh.

This affects downstream: UXARRAY/uxarray#1541

Complete, minimal, self-contained example code that reproduces the issue

import hvplot
hvplot.extension("matplotlib")
print('A:', hvplot.Store.current_backend)
import hvplot.pandas
print('B:', hvplot.Store.current_backend)
hvplot.extension("matplotlib")
print('C:', hvplot.Store.current_backend)
import hvplot.xarray
print('D:', hvplot.Store.current_backend)

Expected hvplot.Store.current_backend to always be "matplotlib". But, these lines actually print out:

A: matplotlib
B: bokeh
C: matplotlib
D: bokeh