Special Characters in Rich Text

Hi, I’m trying to create a text label that has special math symbols in it. For example: ∞
The issue is even with rich text checked, I can’t get these characters to appear in my label. Here’s the HTML reference I’m using.
Is it possible to represent some of these special characters? Do I need a specific font to do this?

If you are using Windows OS you can use that keys Win+. to open a symbol tab where you can find these similar symbols which i suppose should work