Prevent layout shift caused by scrollbars

[gabrieltempass]

Checklist

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• I added a descriptive title and summary to this issue.

Summary

When the content overflows the page and the scrollbar shows up, the content is pushed to the left. Conversely, when the scrollbar disappears, the content is pushed back to the right. Here is an example of the problem:

import streamlit as st


def write_lorem_ipsum():
    st.write(
        """
        Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec eget
        nisi quis augue suscipit tincidunt. Curabitur dignissim tristique ante,
        vitae malesuada augue blandit eget. Duis ullamcorper sit amet augue a
        viverra. Donec orci metus, euismod sit amet pharetra ut, venenatis id
        turpis. Nam scelerisque diam elit, eget sollicitudin ex blandit et. In
        sed quam non massa hendrerit porttitor. Sed vulputate tincidunt
        pulvinar. Vestibulum ante ipsum primis in faucibus orci luctus et
        ultrices posuere cubilia curae; Nunc vehicula ac justo in rhoncus.
        Vestibulum ante ipsum primis in faucibus orci luctus et ultrices
        posuere cubilia curae; Donec nec venenatis elit. Praesent quis
        vulputate nulla, ut dapibus eros. Praesent aliquet leo est, vestibulum
        viverra libero maximus in. Integer eu sollicitudin turpis, quis euismod
        magna.
        """
    )

write_lorem_ipsum()

if st.checkbox("Show more content"):
    write_lorem_ipsum()

And the expected behavior:

Why?

When the content moves from left to right it makes the web app look bad and unprofessional.

How?

There are several ways to avoid this behavior, some better than others, here are a few of them:
https://dev.to/rashidshamloo/preventing-the-layout-shift-caused-by-scrollbars-2flp

Additional Context

No response

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[jrieke]

Especially in the sidebar, this is also pretty annoying because the width is smaller, so it's more noticeable.