feature request: overlay across multiple outputs (multiple displays)

[jason-curtis]

Request

Activate wl-kbptr across all display outputs at once for more fluid usage on multi-display systems.

Background

Currently, in a system with multiple outputs, wl-kbptr only operates on a single display output at a time. This means that the user has to activate the appropriate output before activating wl-kbptr or select the output by CLI input to wl-kbptr. However, at least for floating mode and tile mode, there's no technical reason why we can't just activate overlays on all display outputs at once. The label namespace would be shared - "ab" would have a single target across all displays.

[moverest]

That's a reasonable feature.

Whilst I did think about it, I never bothered because Sway makes it easy to navigate between displays and windows so the added value was small to me for the effort and the complexity it adds. Now that people are using this with other compositors that don't make this as easy it makes a lot of sense to have this.