Checkout from a github repo shows no progress / crashes IDE

Tried to checkout a repo via "Version Control > Checkout".

1. Checkout shows no progress (see attached image). I can see some files in the directory on my machine, but no idea what the status is
2. After about 20 minutes of wondering about the status, the IDE crashed. https://gist.github.com/asb3993/f2500be9086c7a05b21a872407fd45ff

To repo:

1. "Version Control > Checkout"
2. I https'd https://github.com/xamarin/xamarin-android
3. Notice empty dialog box. Wonder about the status. Check the directory – it should be populated.
4. Let the IDE just sit there doing its thing. It should eventually crash.

=== Visual Studio Enterprise 2017 for Mac (Preview) ===

Version 7.1 Preview (7.1 build 1285)
Installation UUID: f7f6f134-fea8-4ebb-ac52-2948e717fb50
Runtime:

	Mono 5.2.0.215 (d15-3/da80840) (64-bit)
	GTK+ 2.24.23 (Raleigh theme)
	Package version: 502000215

=== NuGet ===

Version: 4.3.0.2418

=== .NET Core ===

Runtime: /usr/local/share/dotnet/dotnet
Runtime Versions:

	1.1.1
	1.0.4
	1.0.2

SDK: /usr/local/share/dotnet/sdk/1.0.3/Sdks
SDK Versions:

	1.0.3
	1.0.0-preview2-003148

MSBuild SDKs: /Library/Frameworks/Mono.framework/Versions/5.2.0/lib/mono/msbuild/15.0/bin/Sdks

=== Xamarin.Profiler ===

Version: 1.5.5
Location: /Applications/Xamarin Profiler.app/Contents/MacOS/Xamarin Profiler

=== Xamarin.Android ===

Version: 7.4.0.19 (Visual Studio Enterprise)
Android SDK: /Users/amyb/Library/Developer/Xamarin/android-sdk-macosx

	Supported Android versions:
		4.0.3 (API level 15)
		4.4   (API level 19)
		5.0   (API level 21)
		6.0   (API level 23)

SDK Tools Version: 25.2.5
SDK Platform Tools Version: 25.0.5
SDK Build Tools Version: 25.0.3

Java SDK: /usr
java version "1.8.0_101"
Java(TM) SE Runtime Environment (build 1.8.0_101-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.101-b13, mixed mode)

Android Designer EPL code available here:
https://github.com/xamarin/AndroidDesigner.EPL

=== Apple Developer Tools ===

Xcode 9.0 (13238.4)
Build 9M214v

=== Xamarin.iOS ===

Version: 10.99.6.19 (Visual Studio Enterprise)
Hash: 04e903eb
Branch: xcode9
Build date: 2017-08-31 02:58:55-0400

=== Xamarin Inspector ===

Version: 1.2.2
Hash: b71b035
Branch: d15-1
Build date: Fri, 21 Apr 2017 17:57:12 GMT

=== Xamarin.Mac ===

Version: 3.6.0.17 (Visual Studio Enterprise)

=== Build Information ===

Release ID: 701001285
Git revision: ef4c085256d3b9f3dae9bfb85f7cbd9af6d7d16d
Build date: 2017-08-28 07:06:15-04
Xamarin addins: fd02fc273daf7ff15f74518d971b5ecb1cf8a62d
Build lane: monodevelop-lion-d15-3-xcode9

=== Operating System ===

Mac OS X 10.12.6
Darwin 16.7.0 Darwin Kernel Version 16.7.0

    Thu Jun 15 17:36:27 PDT 2017
    root:xnu-3789.70.16~2/RELEASE_X86_64 x86_64

=== Enabled user installed addins ===

AddinMaker 1.3.7
Manifest.addin 0.0.0.0


Reference: https://bugzilla.xamarin.com/show_bug.cgi?id=59310