Feature idea: Show "where" content elements are used

[liayn]

The mask app already shows how often a content element is used. It would be helpful if this number is clickable and which allows to display the list of pages (incl. uid) where elements are used.

[nhovratov]

This would be a nice feature indeed. Right now I'm focused on Content Blocks development, so no new features will be developed meanwhile. PRs are welcome nevertheless.