Blocklist label in V15

@FransdeJong, we have most of the UI features, but we need Tiptap to reach feature parity with TinyMce, we need tours, some more copy/paste features, and keyboard shortcuts.

As for the backend, the biggest pain point is the sending content/media notifications. There is a discussion going on when people are sharing what they would expect to use. Please contribute here if you have anything relevant: