NSToolbar with translucency in Big Sur

Hi,
I am trying to update my AppKit app for Big Sur, and I'm struggling to figure out how to make the toolbar of my app's window to have the same translucency and background as I see in other apps, like Safari and the Apple Developer app. In my main storyboard, I have created a SplitView-with-Sidebar scene, made the window 'Full Size Content View' and added some toolbar items. If I leave it at that, then the toolbar works as expected. However, if I set the window's titleVisibility to 'NSWindowTitleHidden' (because it looks better), then the translucent effect goes away, and the toolbar has a stark white background.

Is there any way to keep the title hidden but also keep the same translucency effect / background for the toolbar? Again, the Safari and Apple Developer apps are good examples of this.


Thanks.
More details about this issue in question on SO
NSToolbar with translucency in Big Sur
 
 
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