Div container size goes to 0x0 when in initial browser window size

Community Support
3

Unfortunately I have to don’t have time to write an explanation just now but here is a version that works for me, if I understand your ask:

image = Div(text=select.value)

def update_image(url):
    image.text = url

select.on_change('value', lambda attr, old, new: update_image(select.value))

box = column([select], width=300, sizing_mode="fixed")
layout = row(box, image, sizing_mode="stretch_both", name="resize_test")

curdoc().add_root(layout)