What problem does this address?

Currently, when a Navigation Link block is inserted the user sees a Link Control UI in a popover, like this:

If the same block is inserted using the list view in the navigation block, we show the same popover, but in the inspector controls:

This UI is helpful for adding a link. The problem comes when we want to edit that same link. Instead of seeing the same controls again we now show the inspector controls for the Navigation Link block:

This is much less helpful - you have to know the URL of the page you want to link to.

The current approach using popovers is also fragile - there are a couple of issues at least that arise from the fragility:

• Link UI opens in list view for unconfigured Nav Link blocks added via block editor canvas #48028
• Navigation Block: fix link UI popover only opens if there's one navigation block in the page #47829

These two issues highlight that our current approach is using the system in ways that it doesn't support. I think we should reassess the UX here to ensure we are heading in a good direction before we put in too much development time.

What is your proposed solution?

One option is to not use a popover for this at all. Instead we could put the Link Control UI in the inspector controls for the Navigation Link block, something like this:

For this to work we'd need to change the default behaviour of the navigation list view - at the moment when you insert a block, the navigation block stays selected and we don't change the contents of the inspector controls. This raises some more questions:

1. Should we modify the behaviour of all blocks when they are added using the navigation list view, so that they all become selected and the inspector controls update (users can still use the back button to get back to the list view)
2. What should happen when the block is added directly in the canvas?
3. Should we have a different placeholder for the block when it is first added (rather than "Add link")?

Before we put more time into this I'd like to get some design/product input. cc @richtabor @SaxonF @jasmussen @draganescu