Hi, I’m wondering if it is possible to change header colours in a data_editor, I have sort of sections within my table and want to group them but with it all greyscale I can’t.
Also, I seem to be able to change cell colours but not if they are editable, this seems like a weird limitation.
Maybe I’m just missing something but if not, please could I suggest this as a new feature.
Welcome to the community and thanks for your thoughtful question! 
You’re not missing anything—currently, Streamlit’s st.data_editor does not support changing header colors directly, nor does it allow custom background colors for editable cells. Styling via Pandas Styler only works for non-editable columns, and attempts to inject CSS for header styling or editable cell backgrounds are either ignored or overridden by the underlying React component (see here, here, and here). This is a known limitation and has been raised as a feature request by several users.
If you need advanced styling, you might consider alternatives like streamlit-aggrid or streamlit-elements, which offer more flexibility for table customization. For now, you can only style non-editable columns and cells in st.data_editor, and header styling is not supported. If you’d like, you can add your voice to the feature requests on the Streamlit forums to help prioritize this enhancement! Community insights are always welcome—if anyone has a creative workaround, please jump in and share! 
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