Hi,

I ran some tests and found a couple that are failing.  I also checked 
and found these tests don't fail in my 5.1 image.

BrowserTest>>#testBuildMessageCategoryBrowserEditString
DebuggerExtensionsTest>>#testCollectionsGeneralise

I think the first one might actually be a case where a bug was fixed.  
The test fails because of a timeout, because there is a dialog on-screen 
which is not returning.  Not sure, but the test may be intended to 
declare that the dialog should appear, and now it is (?).

The second one, I don't understand.  There is no comment.

Image/VM info:

Squeak6.0alpha
latest update: #17922
Image format 6521 (32 bit)

Virtual Machine
---------------
C:\Users\tcj\Desktop\squeak.cog.spur_win32x86_201803080952\Squeak.exe
Croquet Closure Cog[Spur] VM [CoInterpreterPrimitives 
VMMaker.oscog-eem.2347]
Win32 built on Mar  8 2018 11:08:39 GMT Compiler: 6.4.0
platform sources revision VM: 201803080952

Cheers,
Tim