Panel sizing issue in 3.0.1

Community Support
4

Thanks. Here is a MRE:

import numpy as np
import pandas as pd
from bokeh.models import ColumnDataSource
from bokeh.plotting import figure
from bokeh.layouts import gridplot, column, row, layout
from bokeh.io import show, output_notebook
from bokeh.models import TabPanel, Tabs
#from bokeh.models.widgets import Tabs, Panel

output_notebook()

dates = pd.date_range("20210101", periods=6)
df_1 = pd.DataFrame(np.random.randn(6, 4), index=dates, columns=list("ABCD"))
df_1.rename_axis('Date', axis=0, inplace=True)
source = ColumnDataSource(df_1)

s1 = figure()
s1.line(x='Date',
        y='A',
        source = source,
        color='green')

s2 = figure()
s2.line(x='Date',
        y='A',
        source = source,
        color='green')

s3 = figure()
s3.line(x='Date',
        y='A',
        source = source,
        color='green')

s4 = figure()
s4.line(x='Date',
        y='A',
        source = source,
        color='green')

grid_one = gridplot([[s1,s2], [s3,s4]], sizing_mode='stretch_both', merge_tools=False)
grid_two = gridplot([[s1,s2], [s3,s4]], sizing_mode='stretch_both', merge_tools=False)

tab1 = TabPanel(child=(layout(column(grid_one), sizing_mode='stretch_both')), title="Grid One")
tab2 = TabPanel(child=(layout(column(grid_two), sizing_mode='stretch_both')), title="Grid Two")
    

tabs = Tabs(tabs=[ tab1, tab2 ], css_classes=['custom_tab']) 

show(tabs)