How to make an overlay of all tags

How do I create a global overlay of all tags?

Pressing a shortcut should make all tags appear in seperate boxes in one screen. It should look something like this:

How can I make something like this? How can I seperate tags in boxes?

My collision module or the bling module has something close enough. Getting the exact layout you ask for is non-trivial because AwesomeWM is not a compositing window manager. This means it cannot really take screenshots (let alone live-views) of invisible clients/windows. Usually, the only "safe" thing is to display the outline and client icon.

If you really, really want this, you need:

1. A compositing manager such as picom
2. Either these patches or use gears.surface(client.content) to take a screenshot
3. Lot of code to properly render a wibox with the right screenshots. You can read the bling or collision code to know how to get the size and position.