There was a little (easter egg) next to it because the configuration option was still hidden. It’s been revealed with Streamlit 1.44.0. config.toml - Streamlit Docs
# An array of fonts to use in your app. Each font in the array is a table
# (dictionary) with the following three attributes: family, url, weight,
# and style. To host a font with your app, enable static file serving
# with `server.enableStaticServing=true`. You can define multiple
# [[theme.fontFaces]] tables.
# For example, each font is defined in a [[theme.fontFaces]] table as
# follows:
# [[theme.fontFaces]]
# family = "font_name"
# url = "app/static/font_file.woff"
# weight = 400
# style = "normal"
fontFaces =
More tutorials and explanations will follow shortly.