Dash markdown does not support diff code snippet formatting?

I am generating a diff file using Markdown in Dash:

    return dcc.Markdown('''
` ` `diff
public class Hello1
   public static void Main()
-      System.Console.WriteLine("Hello, World!");
+      System.Console.WriteLine("Rock all night long!");
` ` `

(added spaces in between the ` marks so formating doesn’t mess up)

Ideally the output should resemble something like

When in reality the result looks like this (no formatting):

Screen Shot 2021-03-24

Shouldn’t markdown be able to handle diff formating? If not, has anyone tried to display a diff of content with Dash?