Use hotkey + click to navigate pages in the site editor

[MichaelArestad]

As initially proposed in #19204, I think it would be a good idea to explore navigating pages within the site editor via hotkeys along with perhaps a visual indicator.

Here is a prototype showing what I mean.

Notes

I don't know what hotkey combo we should use. I particularly like the Slack Interface where, if a user holds down Command, the sidebar shows various numbers to let the user know what hotkey combinations do. I think for this purpose, perhaps just holding command could show the user the available links to navigate to by showing a border around them and then just let the user click on them. I'm open to ideas here and I'm no expert on the taken hotkeys or implementation.

Screenshot

Source Figma file

[MichaelArestad]

Related

[mtias]

Folding this into #23328 for easier tracking.