Checklist

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Summary

Add a height parameter to st.chat_input that allows configuring the minimum & initial height of the chat input field.

Why?

It allows the developer to mimic a look & feel that is similar to most of the big LLM-powered apps, e.g. chatgpt:

How?

You can test this feature in this prototype.

st.chat_input(..., height: int | None = None)

• height: Desired minimum height of the UI element expressed in pixels. If this is None (default), uses the default single-line widget height. The height must be at least 40 pixels, which fits one lines. The chat input automatically expands to up to 6.5 lines to accommodate the text value.

Additional Context

No response