qt@5 will be deprecated on 2026-05-19 and disabled 1 year later

[scpeters]

The qt@5 formula is used by Gazebo Ionic and earlier, and since Homebrew/homebrew-core#235319 it is scheduled to be deprecated on 2026-05-19 and disabled one year later. By that time, Gazebo Harmonic will be the only actively supported collection that depends on qt@5.

Options:

1. Drop support for Gazebo Harmonic on macOS with hombrew on 2027-05-19
2. Create and maintain a qt@5 formula in this tap (some security risks to this)

I recommend dropping support for Gazebo Harmonic on macOS (option 1).

[iche033]

I'm also leaning towards 1. Another option would be to disable building the gui, i.e. gz-gui and the gui component in gz-sim. This is probably not a common use case so may not be worth the effort though.