Database | Compare | Multiple Schemas not available via Customize toolbar?

I have a customized toolbar and was trying to add the Multiple Schemas (per the 12 release notes) but doesn’t appear to be available.

I did a Restore Defaults and it appears in the toolbar menu but I lose all my customizations. Is there a way to add it without losing all my customizations?

I found it under [All] after a bit of scrolling.

Does not appear under [Unused] or [New] - which would really be nicer and more intuitive.