This is going to sound odd, but in your screenshot above, I notice you have the backdrop turned on.
What if you turn off the 'backdrop' in the view menu?
Does every window of the IDE continue to steal focus still?
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It doesn't make any difference as far as I can tell - at least from my testing on 10.9 up to 10.15 Catalina.
I don't have a Monterey mac to test on.
You can see how I'm still able to put the 'System preferences' window in front of the untitled stack window, no matter if the backdrop is on or off.
I just wonder if it's doing something weird on MacOS 12 Monterery for you, perhaps because it doesn't like the backdrop (?) - just a guess at this stage.
Second issue:
sounds a strange question - but the version you are getting that error on, isn't that 0.98 or lower?
The reason I ask is: (to be cheeky and re-use your screenshot you sent)
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I sorted this tool icon out in 0.99 on the mac, so I guess you are running an earlier 0.98 - If so, that has an older copy of revMenubar with conflicting shortcuts.
In version 0.98, I found this conflicted with "revshortcutslibrary.livecodescript"
Or rather, to be more accurate: "revshortcutslibrary.livecodescript" contained statements that were conflicting with the revmenubar.livecodescript stack - they were both trying to set their own values at the same time and fighting for control.
This makes sense, as I was messing about with the 'file' > 'save as' shortcuts in 0.98, and didn't know about this nasty surprise left for me in the revshortcutslibrary.
So, by changing the 'save as' shortcut in the file menu, I would have unknowingly triggered this error and produced a conflict.
This also explains why LCC 9.6.3 and OXT Lite 0.97 and lower didn't produce this error.
This could be exactly why you are getting that NSMenu error, if it turns out you are running an older version - (0.98 specifically)
I have a vague theory that 0.98 was locking up Richmond's mac because of this same issue too.
I had a look at the menu C++ code today, and it appears that the menus on the Mac are drawn with a cocoa API. (Surely that had been phased out). The Mac part of the menu code also contains statements like 'it does this for some unknown reason'.
The Windows and Linux parts of this menu code don't use any cocoa API - that's a Mac thing only), and because they are coded differently, they seem a lot more forgiving of conflicting shortcuts.
Anyway, that's my theory at the moment.
Theories are all well and good, but they need proving.
Either way, I fixed all those conflicts in 0.99 and above, so if you can confirm which version of the IDE this is please that would be great. I'm pretty sure it's something before v0.99.