Summary

Error thrown when using st.code with an empty string.

Steps to reproduce

What are the steps we should take to reproduce the bug:

1. Run a script with a st.code statement like this:

st.code("")

Expected behavior:

no error

Actual behavior:

An exception stack trace is shown in the browser

Is this a regression?

not sure

Debug info

On Chrome 77.0.3865.75 and develop:b6734272dbc22cad24520be190d0554921d46e2a
MacOs 10.4.6