In NSColorPanel, when I dragging the selected color into Color Favourites List, the application crash

This problem only occurs when NSColorPanelSwatches.plist doesn’t exist and OS Version is MacOS BigCur.

When I use Swift to Create the same View and do the same action, the question will not occurs.

Is this a problem with the Appkit in Xamarin.Mac？

Or did I forget some initial settings?

var colorPanel = NSColorPanel.SharedColorPanel;
colorPanel.Color = NSColor.FromSrgb(color.Red / 255f, color.Green / 255f, color.Blue / 255f, 1.0f);
NSApplication.SharedApplication.RunModalForWindow(colorPanel);

I build this app in the following environment

• OS:10.15.5
• Xamarin.Mac:6.18.2.1
• Xcode:11.4.1
• Mono:6.10.0.104

crash information:

• Assertion failed: (backingScaleFactor > 0.f), function drawnFocusRingBitmapForTime, file /AppleInternal/BuildRoot/Library/Caches/com.apple.xbs/Sources/AppKit/AppKit-1997/AppKit.subproj/NSAutomaticFocusRing.m, line 298.