HTML Editor Isn't Appearing in the Admin Panel

I've never had this problem before with other sites, but for some reason the advanced editor that allows you to insert HTML into widgets, forum descriptions, etc. isn't showing up. I've enabled HTML on my forum, and I've gone through the admin panel over and over again searching for the option to allow it, but I can't find it. Can anyone help me out with this?

You mean this button above the text box ? Display>Generalities
Homepage, message content:

Yes, that button! How do I get it to appear?

So basically the codes you insert in the HTML aren't working. Or the editor isn't showing up? Have you try pressing the HTML button? Can you show me a screenshot of what you're looking for. Thanks

I think its because you are using google chrome. Its a known issue.

Try firefox, it shall appear.

Oh, okay! It worked, thank you!