Implement MarkdownColumn

[rgajrawala]

Describe your changes

I want to display bolded/italicized/underlined parts of text in my dataframe table. So we can use the MarkdownCell from Glide Data Grid.

Others also have similar requests - https://discuss.streamlit.io/t/how-to-display-st-markdown-in-a-column-of-st-dataframe/59301.

GitHub Issue Link (if applicable)

Testing Plan

• Explanation of why no additional tests are needed
• Unit Tests (JS and/or Python)
• E2E Tests
• Any manual testing needed?

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[rgajrawala]

I didn't see any docs on building streamlit to test changes. Can someone please point me to some docs?

[jrieke]

Hey @rgajrawala! PM from the Streamlit team here. Thanks for the contribution! Lukas (our eng who's working on most dataframe things) is currently out of office but I'll let him have a look when he's back. I think we considered markdown cells in the past but decided against it. I am not entirely sure anymore what the reason was, but I think it was related to markdown cells only showing the formatted markdown text when you double-click in Glide, which is a bit confusing.

Would you mind describing your use case a bit more, i.e. what kind of text you're trying to show and why it needs to be formatted in this way? Also, is it ok for you if this formatting only shows up when you double click the cell or do you want to have it always displayed?

[rgajrawala]

Hi @jrieke, yes the markdown will only show in the overlay, which is okay for my usecase (showing some text with some parts highlighted). Currently I have to display this info in a separate HTML table from my numerical data in a dataframe table, and I'd like to join the functionality.

[rgajrawala]

Hi @jrieke, do you know when @LukasMasuch will be back? I'd like to get this in soon if possible.