Inserting unicode character

I want to add the pause sign to a font. The unicode is 23F8. I tried adding a new glyph with the name ‘pause’, but that doesn’t work. How should I call this glyph?

If you know the Unicode, you can call it uni23FB and it will be automatically renamed to the nice glyph name.

If you want to find out the nice glyph name yourself, see Window > Glyph Info and search for the Unicode. This way, you can find out that its name is doubleVerticalBar.