[UIXPRESS] Add search option to custom css editor

I have close to 1000 lines of code in my custom css stylesheet and it’s getting bigger every day. But working with the css editor is not a very exciting thing to do.

If I search for a specific style, I scan through hundreds of lines of code. A search option would be a huge time saver. Chrome also can’t be used for searching, because it does not recognize the modal the css editor is placed in.