The display panel can turn a monitor off again
The per-display switch in the display panel did nothing, and the panel still reported success. Pull request 13725 merged into quattro.
The toggle used hyprctl keyword, which current Hyprland rejects while still exiting without an error. The panel now uses the monitor eval command the scaling tool already uses.
The pull request says this was reproduced on version 4.0.4. The GitHub user houz42 opened pull request 13725, and David Heinemeier Hansson merged it.