Issue with Rhino 8 and macOS Alt-Tab app Affecting Multitasking

Hello Rhino Development Team,

I would like to bring to your attention an issue I’ve encountered with Rhino 8 on macOS, specifically related to multitasking with the Alt-Tab application switcher.

Description of the Issue: While using Alt-Tab on macOS with Rhino 8, I’ve noticed that two separate instances appear for Rhino 8: the main software window and the command line interface. Ideally, the command line should not be displayed as a distinct window in the Alt-Tab switcher. This behavior significantly impacts multitasking efficiency on macOS.

I raised this issue with the Alt-Tab developers and after their analysis, it was concluded that the issue lies within Rhino 8’s implementation. The detailed response from the Alt-Tab team can be found in this GitHub issue: Alt-Tab macOS Issue #3218.

Response from Alt-Tab Developer: The Alt-Tab developer mentioned that Rhino 8 appears to be using an actual window to implement what should ideally be a tooltip or a non-window element. This is a common issue with applications ported from other platforms or using cross-platform UI libraries. Unfortunately, from the Alt-Tab side, there is no workaround other than entirely blacklisting the application, which is not a feasible solution.

Request for Resolution: Given the critical importance of efficient multitasking on macOS, I kindly request the Rhino development team to investigate and address this issue. Resolving it would significantly enhance the user experience for many Rhino users on macOS, especially those who rely on the Alt-Tab functionality for their workflow.

Thank you for your attention to this matter. I am looking forward to a possible solution that enhances Rhino 8’s compatibility and usability on macOS.

Best regards,
Giulio Minuto

I don’t see a second window when I have one document open. I see just the one Rhino 8 window

Thank you for your response. After further investigation, I’ve realized that my issue is triggered by a specific behavior in Rhino 8. This involves the frequent appearance of a debug string in the command line window. This occurs not only sporadically during normal operation but also consistently each time I switch to Rhino using Alt-Tab. Additionally, it sometimes happens when another window is “on top”, causing Rhino to come to the foreground. This string is logged, without any direct action from my side.

For example, entries like these are common:

  • “2024.03.05 19:30:42.124 +01:00 [301 | DEBUG | in [055] returns: 0 bytes (NoCleanup)”
  • “2024.03.05 19:32:10.990 +01:00 [1] | DEBUG | out [078] Cad_Environment_HostApplicationDeactivated: 8 bytes”
  • “2024.03.05 19:32:10.990 +01:00 [11] | DEBUG | in [078] returns: 0 bytes (NoCleanup)”
  • “2024.03.05 19:32:11.518 +01:00 [1] | DEBUG | out [079] Cad_Environment_HostApplicationActivated: 8 bytes”
  • “2024.03.05 19:32:11.519 +01:00 [31] | DEBUG | in [079] returns: 0 bytes (NoCleanup)”

It seems that these debug messages are causing a command line window to open and be recognized as a separate window by the macOS Alt-Tab application.



I think this may have already changed in Rhino 8.6, I have now a command-history docked at the bottom and I don’t think I’m getting these tooltips popping up anymore.

Perfect, thank you for the update. Could you please inform me if there’s a way to download a preview versions like 8.6, or do we have to wait for the official release?

Typically every second Tuesday of the month we make service releases, and with that the first service release candidate for what will become the next service release. So if all goes right Rhino 8.6 service release candidate will be available next week Tuesday.